IuGW architecture with RTP localization

ABSTRACT

A method for localizing a voice call is disclosed, comprising: receiving an originating leg setup message for an originating leg bearer from the first base station for a first user equipment (UE); creating a first call correlation identifier and storing the first call correlation identifier in association with the first UE; extracting a second call correlation identifier from a terminating leg setup message for a terminating leg bearer received from the core network; determining a real time protocol (RTP) localization status for the originating leg bearer and the terminating leg bearer based on matching the second call correlation identifier of the terminating leg against the stored first call correlation identifier of the originating leg; and sending transport layer assignment messages to the first base station to redirect RTP packets from the first UE to the second UE via the terminating leg bearer without the RTP packets transiting the core network.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of, and claims priority under 35U.S.C. § 120 to, U.S. patent application Ser. No. 16/444,704, filed Jun.18, 2019, which itself is a non-provisional conversion of, and claimspriority under 35 U.S.C. § 119(e) to, U.S. Provisional Pat. App. No.62/398,201, titled “RTP Localization for Multi-Core Networks,” and filedon Sep. 22, 2016, and also a continuation of U.S. patent applicationSer. No. 15/713,584, “IUGW Architecture With RTP Localization,” filedSep. 22, 2017, which itself is a continuation-in-part of, and claimspriority under 35 U.S.C. § 120 to, U.S. patent application Ser. No.15/464,333, titled “IuGW Architecture” and filed on Mar. 20, 2017,itself a non-provisional conversion of U.S. Provisional Pat. App. No.62/310,173, each hereby incorporated by reference in its entirety forall purposes.

This application also hereby incorporates by reference U.S. Pat. No.8,879,416, “Heterogeneous Mesh Network and Multi-RAT Node Used Therein,”filed May 8, 2013; U.S. Pat. No. 9,113,352, “HeterogeneousSelf-Organizing Network for Access and Backhaul,” filed Sep. 12, 2013;U.S. Pat. No. 8,867,418, “Methods of Incorporating an Ad Hoc CellularNetwork Into a Fixed Cellular Network,” filed Feb. 18, 2014; U.S. patentapplication Ser. No. 14/034,915, “Dynamic Multi-Access Wireless NetworkVirtualization,” filed Sep. 24, 2013; U.S. patent application Ser. No.14/289,821, “Method of Connecting Security Gateway to Mesh Network,”filed May 29, 2014; U.S. patent application Ser. No. 14/500,989,“Adjusting Transmit Power Across a Network,” filed Sep. 29, 2014; U.S.patent application Ser. No. 14/506,587, “Multicast and BroadcastServices Over a Mesh Network,” filed Oct. 3, 2014; U.S. patentapplication Ser. No. 14/510,074, “Parameter Optimization and EventPrediction Based on Cell Heuristics,” filed Oct. 8, 2014, U.S. patentapplication Ser. No. 14/642,544, “Federated X2 Gateway,” filed Mar. 9,2015, and U.S. patent application Ser. No. 14/936,267, “Self-Calibratingand Self-Adjusting Network,” filed Nov. 9, 2015, each in its entiretyfor all purposes. This document also hereby incorporates by referenceU.S. Pat. Nos. 9,107,092, 8,867,418, and 923,547 in their entirety. Thisdocument also hereby incorporates by reference U.S. patent applicationSer. No. 14/822,839 in its entirety.

BACKGROUND

In the Third Generation (3G) Universal Mobile Telecommunications System(UMTS) system, when a voice call is established from one mobilesubscriber to another mobile subscriber, even though both the mobilesubscribers are camped on to the same base station or NodeB, thesignaling and RTP messages flow between mobile subscribers and mobileoperators' core networks via a base station and a radio networkcontroller over a wired or wireless backhaul system. This causesinefficient use of backhaul bandwidth and blocking of various types ofresources at radio network controllers and core networks.

SUMMARY

Systems and methods for a telecommunications network are disclosed.

In a first embodiment, a method may be disclosed, comprising: at acoordinating server situated as a gateway between a first base stationand a core network, receiving an originating leg setup message for anoriginating leg bearer from the first base station for a first userequipment (UE) attached to the first base station, the first UEregistered with the coordinating server, sent when the first UEinitiates a voice call to a second UE, the second UE also registeredwith the coordinating server; creating a first call correlationidentifier and storing the first call correlation identifier inassociation with the first UE; extracting a second call correlationidentifier from a terminating leg setup message for a terminating legbearer received from the core network; determining a real time protocol(RTP) localization status for the originating leg bearer and theterminating leg bearer based on matching the second call correlationidentifier of the terminating leg against the stored first callcorrelation identifier of the originating leg; and sending transportlayer assignment messages to the first base station to redirect RTPpackets from the first UE to the second UE via the terminating legbearer without the RTP packets transiting the core network, therebylocalizing the RTP packets.

The method may further comprise encoding the first call correlationidentifier into the originating leg setup message. The setup message maybe a non-access stratum (NAS) setup message, the first base station maybe a nodeB, the bearer modification message may be a Universal MobileTelecommunications Service (UMTS) radio access bearer (RAB) modificationmessage. The first call correlation identifier may be encoded in aUser-User information element (IE) in the originating leg setup message,and The method may further comprise forwarding, by the core network, theoriginating leg setup message as the terminating leg setup message. Thetransport layer assignment messages to the first base station include anInternet Protocol (IP) address of a serving base station for the secondUE, and The method may further comprise sending transport layerassignment messages to the serving base station for the second UE toredirect second RTP packets from the second UE to the first UE via theoriginating leg bearer without the second RTP packets transiting thecore network.

The method may further comprise performing radio access bearer (RAB)modification based on the determination of the RTP localization statusby sending RAB assignment requests to the base station for the first UE,and The transport layer assignment messages may be RAB modificationmessages. The second UE may be also attached to the first base station,and The method may further comprise performing radio access bearer (RAB)modification based on the determination of the RTP localization statusby sending RAB assignment requests to the base station for the first UEand the second UE. The second UE may be also attached to the first basestation and the RTP packets may be redirected internally within thefirst base station. The first base station and the second base stationmay be a single base station using a single radio access technology.

The method may further comprise redirecting the RTP packets as an RTPstream routed from the first base station to a second base station via amesh network. The method may further comprise sending comfort noise RTPpackets to the core network from the coordinating server based on thedetermination of the RTP localization status. The first call correlationidentifier may be generated based on an equipment identifier of, or anInternet Protocol (IP) address of, a caller and a called party. Thefirst call correlation identifier may be generated based on a radio areanetwork (RAN) identifier of the base station. The method may furthercomprise receiving a Relocation Required message from the first basestation for the first UE in a RTP localized call between the first UEand the second UE, caused by the first UE being handed over to a secondbase station.

The method may further comprise providing an inter-RAT handover of thefirst UE to one of a Wi-Fi radio access technology (RAT), a Long TermEvolution RAT using Voice over LTE (VoLTE), or a 2G RAT, and providingtranscoding of the RTP packets to enable the inter-RAT handover. Themethod may further comprise: creating, at the coordinating server, anassociation between an International Mobile Subscriber Identity (IMSI)of the second UE and a Mobile Station International Subscriber DirectoryNumber (MSISDN) of the second UE; creating the first call correlationidentifier based on a called party MSISDN; receiving the terminating legsetup message from a core network, the terminating leg setup messagecontaining an IMSI of the second UE; extracting the second callcorrelation identifier by retrieving the MSISDN of the second UE basedon the association of the IMSI and MSISDN of the second UE at thecoordinating server; and performing a comparison of the called partyMSISDN and the MSISDN of the second UE at the coordinating server todetermine a RTP localization status. The method may further compriserequesting an International Mobile Subscriber Identity (IMSI) of thefirst UE and a Mobile Station International Subscriber Directory Number(MSISDN) of the first UE from a provisioning server using a HyperTextTransfer Protocol web services protocol. The method may further compriseproviding billing and policy enforcement of the RTP packets without theRTP packets transiting the core network.

The method may further comprise providing lawful intercept of the RTPpackets by copying the RTP packets and sending the copied RTP packets tothe core network asynchronously. The method may further compriseproviding lawful intercept of the RTP packets by sending compressed RTPpackets to the core network.

In a second embodiment, a non-transitory computer-readable medium isdisclosed, which, when executed on a processor, causes the processor toperform steps comprising: at a coordinating server situated as a gatewaybetween a first base station and a core network, receiving anoriginating leg setup message for an originating leg bearer from thefirst base station for a first user equipment (UE) attached to the firstbase station, the first UE registered with the coordinating server, sentwhen the first UE initiates a voice call to a second UE, the second UEalso registered with the coordinating server; creating a first callcorrelation identifier and storing the first call correlation identifierin association with the first UE; extracting a second call correlationidentifier from a terminating leg setup message for a terminating legbearer received from the core network; determining a real time protocol(RTP) localization status for the originating leg bearer and theterminating leg bearer based on matching the second call correlationidentifier of the terminating leg against the stored first callcorrelation identifier of the originating leg; and sending transportlayer assignment messages to the first base station to redirect RTPpackets from the first UE to the second UE via the terminating legbearer without the RTP packets transiting the core network, therebylocalizing the RTP packets.

In a third embodiment, a computer-implemented method is disclosed,comprising, at a coordinating server comprising a RTP localizationmodule receiving a first non-access stratum (NAS) Setup message from abase station for an originating leg where the base station sends NASSetup message to the coordinating server when a first user equipment(UE1) registered with the coordinating server and camped on the basestation initiates a voice call to a second user equipment (UE2), the UE2may be registered to the coordinating server and camped on the basestation; creating a call correlation-id to encode in a User-UserInformation Element (IE) for a message to send to a core network;decoding a received NAS Setup message from the core network to extract acall correlation-id from a User-User IE in the received NAS Setupmessage; finding a record for the call correlation-id from the receivedNAS Setup message; determining a RTP localization status finding basestations based on call correlation-id related to the mobile originatingleg and the received NAS Setup message from the core network related toa mobile terminating leg; and performing radio access bearer (RAB)modification based on the determination of the RTP localization statusby sending RAB assignment requests to the base station for the UE1 andthe UE2.

The method may further comprise sending comfort noise RTP packets to thecore network from the coordinating server based on the determination ofthe RTP localization status. The call correlation ID to encode in theUser-User Information Element (IE) for the message to send to the corenetwork may be generated based on a called party address information.The call correlation ID to encode in the User-User Information Element(IE) for the message to send to the core network may be generated basedon an IP address of the base station. The call correlation ID to encodein the User-User Information Element (IE) for the message to send to thecore network may be generated based on a radio area network (RAN)identifier of the base station. The call correlation ID to encode in theUser-User Information Element (IE) for the message to send to the corenetwork may be stored in a random-access memory. The call correlation IDto encode in the User-User Information Element (IE) for the message tosend to the core network may be stored in a database.

The method may further comprise receiving a Relocation Required from thebase station for at least one of a user equipment (UE) in a RTPlocalized call between the UE1 and the UE2 with at the base stationmoving to a second base station. The method may further compriseperforming RAB modification for a user equipment (UE) in the RTPlocalized call between the UE1 and the UE2 at the base station and theUE remains camped on to the base station.

In a fourth embodiment, a computer-implemented method is disclosed,comprising: at a coordinating server comprising a RTP localizationmodule registering to a provisioning gateway; receiving a user equipmentregistration request at the coordinating server; sending a query requestto the provisioning gateway to create an association between anInternational Mobile Subscriber Identity (IMSI) and a Mobile StationInternational Subscriber Directory Number (MSISDN); and receiving aquery response from the provisioning gateway and creating theassociation between the IMSI and the MSISDN.

The method may further comprise receiving from a core network a NASSetup message for a mobile terminated call; performing a comparison of acalling party MSISDN in the received NAS Setup message a calling partyMSISDN for a mobile originated call the coordinating server to determinea RTP localization status; and performing a radio access bearer (RAB)modification based on the determination of the RTP localization status.The query request may be sent using SOAP web services. The query requestmay be sent using REST web services.

In a fifth embodiment, a method may be disclosed, comprising: detecting,at a gateway, a packet-based voice session with a source base stationand a target base station, the source base station being attached to anoriginating user equipment and the target base station being attached toa terminating user equipment, the source base station and the targetbase station each being coupled to a core network via the gateway;performing, at the gateway, endpoint lookup of the terminating userequipment; and redirecting, via the gateway, call audio of thepacket-based voice session to the terminating user equipment from apathway through the core network to a pathway through the gateway.

The source base station and the target base station may be a single basestation and the packet-based voice session may be terminated at thesource base station. The packet-based voice session may be a real timeprotocol (RTP) voice session. The packet-based voice session may becircuit-switched or packet-switched. The packet-based voice session maybe routed using hairpin routing. The packet-based voice session may be acircuit-switched fallback (CSFB) call. The method may further compriseperforming endpoint lookup using a phone number of the terminating userequipment. The method may further comprise redirecting the call audio ofthe packet-based voice session within a group of base stations or acrossmultiple groups of base stations. The group of base stations or multiplegroups of base stations may be managed by the gateway. The method mayfurther comprise redirecting the call audio of the packet-based voicesession from a 2G or 4G base station to a 3G base station. The methodmay further comprise redirecting the call audio of the packet-basedvoice session from a 2G or 3G base station to a 4G base station. Themethod may further comprise providing, at the gateway, three-waycalling, call hold, call conferencing, or improved voice quality for thepacket-based voice session. The method may further comprise reducingbandwidth required on a link between the gateway and the core network.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A and 1B are network architecture diagrams for prior art 3GPP 3Gnetworks.

FIG. 2 is a schematic network architecture diagram for 3G and other-Gprior art networks.

FIG. 3 is a schematic network architecture in accordance with someembodiments.

FIG. 4 is a schematic network architecture in accordance with somefurther embodiments.

FIG. 5 is a schematic network architecture showing security andsignaling characteristics in accordance with some embodiments.

FIG. 6 is a schematic network architecture showing base station groupingin accordance with some embodiments.

FIG. 7 is a schematic base station deployment topology diagram, inaccordance with some embodiments.

FIG. 8 is a signaling call flow showing a handover of a circuit-switchedsession at a gateway, in accordance with some embodiments.

FIG. 9 is a signaling call flow showing a handover of a packet-switchedsession at a gateway, in accordance with some embodiments.

FIG. 10 is a signaling call flow showing a two-phase macro to rural zonemobility scenario, in accordance with some embodiments.

FIG. 11 is a signaling call flow showing an Iuh anchored rural to ruralzone mobility scenario, in accordance with some embodiments.

FIG. 12 is a signaling call flow showing additional aspects of a ruralto rural zone mobility scenario, in accordance with some embodiments.

FIG. 13 is a signaling call flow showing base station registration, inaccordance with some embodiments.

FIG. 14 is a schematic architecture diagram of an exemplary base stationtogether with an exemplary gateway, in accordance with some embodiments.

FIG. 15 is a signaling call flow showing handin with call connectmessage forking, in accordance with some embodiments.

FIG. 16 is a schematic network architecture diagram showing RTPlocalization, in accordance with some embodiments.

FIG. 17 is a schematic architecture diagram of an exemplary gateway, inaccordance with some embodiments.

FIG. 18 is a schematic architecture diagram of an exemplary basestation, in accordance with some embodiments.

FIG. 19 is a prior art network diagram of a deployment scenario.

FIG. 20 is a network diagram showing signaling and RTP path betweenvarious network components, in accordance with some embodiments.

FIG. 21 is a call flow ladder diagram for RTP localization, inaccordance with some embodiments.

FIG. 22 is a call flow ladder diagram for RTP localization, inaccordance with some embodiments.

FIG. 23 is a call flow ladder diagram for RTP localization, inaccordance with some embodiments.

FIG. 24 is a network diagram for a mobility scenario, in accordance withsome embodiments.

FIG. 25 is a network diagram for a mobility scenario, in accordance withsome embodiments.

FIG. 26 is a call flow ladder diagram when a RTP localizationfunctionality is terminated, in accordance with some embodiments.

FIG. 27 is call flow ladder diagram for RTP localization, in accordancewith some embodiments.

FIG. 28 is a call flow diagram when RTP localization is enabled using anIMSI and a MSISDN mapping, in accordance with some embodiments.

FIG. 29 is a flowchart of RTP localization activation procedure, inaccordance with some embodiments.

FIG. 30 is a flowchart of RTP localization activation procedure, inaccordance with some embodiments.

FIG. 31 is a flowchart of RTP localization deactivation procedure, inaccordance with some embodiments.

DETAILED DESCRIPTION

The detailed description set forth below is intended as a description ofvarious configurations of the subject matter and is not intended torepresent the only configurations in which the subject technology may bepracticed. The appended drawings are incorporated herein and constitutea part of the detailed description. The detailed description includesspecific details for the purpose of providing a thorough understandingof the subject technology. However, it will be clear and apparent tothose skilled in the art that the subject technology is not limited tothe specific details. In some instances, well-known structures andcomponents are shown in block diagram form in order to avoid obscuringthe concept of the subject technology.

Overview

Through its HetNet Gateway (HNG) (TM), the Parallel Wireless solutioncan orchestrate and manage the Radio Access Network (RAN) acrossmultiple technologies, including 3G, 4G and Wi-Fi, with high ease ofuse. The centerpiece of the Parallel Wireless solution is the HetNetGateway, which is the wireless industry's first carrier-grade,high-performance RAN orchestrator that is based on software-definednetworking (SDN) and network functions virtualization (NFV), and is 100percent compliant with all open and standard interfaces as defined bythe 3rd Generation Partnership Project (3GPP). The Parallel Wireless HNGvirtualizes the RAN interfaces to manage the 4G and 3G (Long TermEvolution, or LTE, and universal mobile telecommunications system, orUMTS) RANs (HomeNodeBs/NodeBs and eNodeBs/HeNodeBs) in real-time viamulti-technology self-organizing network (SON) and gateway functionalitywhile abstracting RAN changes from the core network and the core networkitself from the RAN. The Parallel Wireless HNG virtualizes thousands ofbase stations to look like a smaller number of virtualized “boomercells” to the core. The Parallel Wireless HNG also virtualizes radionetwork nodes such as Wi-Fi access points (APs), eNodeBs and NodeBs andmakes them self-configurable, self-adjustable, and self-healing, helpingwith initial installation and ongoing maintenance. The Parallel WirelessHNG acts like a virtual radio network controller (vRNC or virtual RNC)for multi-RAT network handling resources for different technologies 3G,LTE/4G and WiFi while optimizing call processing towards radio and corenetwork elements such as the mobile switching center (MSC), servingglobal packet radio system (GPRS) support node (SGSN), gateway GPRSsupport node (GGSN), evolved packet core (EPC) for 4G, home subscriberserver (HSS), and policy charging and rules function (PCRF).

Paired with the Parallel Wireless HNG, the Parallel Wireless basestation, the Converged Wireless System (CWS) (TM), is a multi-RAT basestation with LTE, Wi-Fi, and 3G technologies that provides a flexibleoutdoor and in-vehicle solution in conjunction with the ParallelWireless HNG. The combined system is a cloud-based network orchestrationsystem that maximizes virtualization, and functions in a 3GPPstandards-based Heterogeneous Network (HetNet) to bring 3G, Wi-Fi and 4Goperators better technology at lower cost. The Parallel Wirelesssolution addresses key challenges in delivering 3G/4G coverage,capacity, and quality of service (QoS), regardless of the cell size,e.g., femtocell, pico cell, micro cell, metro cell, or macro cell. TheParallel Wireless solution is also easy to deploy with automatedconfiguration and ongoing optimization.

This disclosure covers a 3G vRNC/HNBGW solution provided by the ParallelWireless HNG. This disclosure also captures architecture and call flowdetails for an IuGw feature. The proposed IuGw sits in between a basestation, such as the Parallel Wireless CWS (which acts as an HNB), and acore network, which may include an external HNBGW on the Iuh interface.To the CWS (HNB) the IuGW acts as and virtualizes an HNBGW, and to HNBGWit acts as a virtual HNB. The system is generalizable to provideinteroperability among any-G RAN access nodes with various combinationsof core networks, including with a combined 3G and a 4G core network.

Architecture with an IuGw plus Iub over IP to MSC.

Using the architecture described herein, it is possible to enable 3Gpacket and circuit calling and data over IP with a flexible and scalablearchitecture. A gateway, called variously the Parallel Wireless HNG orParallel Wireless HNG, acts as a 3G radio network controller (RNC) andprovides one or more virtualized nodeBs as needed using grouping andmapping. It interfaces with an existing MSC, SGSN via IuCS, IuPS, insome embodiments. The advantages of this architecture include thehelpful features of virtualized cells, here, virtual nodeBs, as with theParallel Wireless LTE virtualization scheme. Also, significantly, usingthis architecture it is possible to provide an all-IP RAN, with fewerlegacy interfaces provided at the core network. This architecture may beadapted for various use cases: emergency services, Band 14 services,multi-operator core networks (MOCN). Iu-Flex can be used for 3G MOCN ormulti-MSC, or to provide resiliency across data centers.

As compared to the use of femto cells in an existing network, CWS isvery different from femto in scale, RF power/coverage area andcapabilities; femto needs external AAA but this architecture does not;femto capacity is additive on top of current network, as opposed to noadditional cost with Parallel Wireless HNG; with Parallel Wireless HNGconnecting to MSC/SGSN it can provide better 911/LBS solution;simplified network architecture at low cost/Cleaner integration; andthis CWS/Parallel Wireless HNG solution is not a femto solution hencedoes not need femto GW. The CWS solution is ideal for a greenfieldscenario, providing both 3G and 4G connectivity, in conjunction with theParallel Wireless HetNet Gateway. However, the CWS and HNG may also beleveraged to provide effective brownfield network architectures. Inother words, in a greenfield scenario, it is possible to convert any-Gto proprietary Iuh.

The following references are incorporated by reference in theirentirety: UTRAN Overall Description—3GPP TS 25.401 V8.2.0 (2008December) [1]; UTRAN Architecture for 3G Home Node B—3GPP TS 25.467V.8.10 (2009 March) [2]; 3GPP TS 29.281 GPRS Tunneling Protocols—UserPlane (GTP-U) [3]; 3GPP TS 29.060 GPRS Tunneling Protocol [4]; 3GPP TS25.413 RANAP Signalling [5]; 3GPP TS 23.003 Numbering, Addressing andIdentification [6]; 3GPP TS 25.468—UTRAN Iuh Interface RANAP UserAdaption (RUA) Signaling [7]; 3GPP TS 25.469—UTRAN Iuh Interface RANAPUser Adaption (HNBAP) Signaling [8].

FIGS. 1A and 1B are network architecture diagrams for prior art 3GPP 3Gnetworks. FIG. 1A shows a 3GPP UTRAN architecture. FIG. 1B shows a 3GPPHome NodeB (femto) architecture. As shown in FIG. 1A, the 3GPP UTRANarchitecture includes a mobile station 101, a nodeB 102 (also known as abase transceiver station or BTS), a radio network controller (RNC) 103,and a mobile core 106, the mobile core including a serving GPRS supportnode (SGSN) 104 and a mobile switching center (MSC) 105. The RNCperforms functions that include radio resource control, assigningscrambling codes to UEs, power control, ciphering, Kasumi (UE to RNC;note that nodeB connection is not assumed to be secure), and otherfunctions. The MSC acts as a telephone exchange that makes theconnection between mobile users within the network, from mobile users tothe public switched telephone network and from mobile users to othermobile networks. The MSC also administers handovers to neighbouring basestations, keeps a record of the location of the mobile subscribers, isresponsible for subscriber services and billing. The Serving GPRSSupport Node (SGSN) is a main component of the GPRS network, whichhandles all packet switched data within the network, e.g. the mobilitymanagement and authentication of the users. The SGSN performs the samefunctions as the MSC for voice traffic. Between the MS 101 and nodeB 102is a Uu air interface, between the nodeB and the RNC is an Iubinterface, and between the RNC and the core are two interfaces, IuPS andIuCS. IuPS is the interface used for packet-switched connections. IuCSis the interface used for circuit-switched connections, which in 3Ginclude phone calls.

FIG. 1B shows a 3GPP femto architecture, which is similar to FIG. 1A.This architecture includes a mobile station 111, a nodeB 112 (also knownas a base transceiver station or BTS), a radio network controller (RNC)113, and a mobile core 116, the mobile core including a serving GPRSsupport node (SGSN) 114 and a mobile switching center (MSC) 115. Whilethe Uu interface is unchanged, the interface between the BTS and RNC isIuh instead of Iub, and also includes an IPsec tunnel between the nodes.The Iub interface is an interface and protocol that allows a macro basestation to control the majority of the functions of a nodeB, exceptbaseband and analog-digital conversion. Iub includes control mechanismsto allow an RNC to directly control a NodeB to do all of the following:resource management; scheduling; encryption/decryption; power control;etc. In 3GPP, a regular nodeB does not perform encryption. Iub can beused over IP transport. Iuh is a more lightweight protocol allowing for,e.g., radio resource management at a HNB or femto cell itself. While itis useful to enable a base station to But for carriers with existingmacros deployed, it does not make sense to switch already-deployed macrobase stations using Iub to Home nodeBs using Iuh; as well, macro basestations have coverage advantages. However, the two interfaces aresimilar because both Iub and Iuh terminate at a RNC.

FIG. 2 is a schematic network architecture diagram for 3G and other-Gprior art networks. The diagram shows a plurality of “Gs,” including 2G,3G, 4G, and Wi-Fi. 2G is represented by GERAN 201, which includes a 2Gdevice 201 a, BTS 201 b, and BSC 201 c. 3G is represented by UTRAN 202,which includes a 3G UE 202 a, nodeB 202 b, RNC 202 c, and femto gateway(FGW, which in 3GPP namespace is also known as a Home nodeB Gateway orHNBGW) 202 d. 4G is represented by EUTRAN 203, which includes an LTE UE203 a and LTE eNodeB 203 b. Wi-Fi is represented by Wi-Fi access network204, which includes a trusted Wi-Fi access point 204 c and an untrustedWi-Fi access point 204 d. The Wi-Fi devices 204 a and 204 b may accesseither AP 204 c or 204 d. In the current network architecture, each “G”has a core network. 2G circuit core network 211 includes a 2G MSC/VLR;2G/3G packet core network 212 includes an SGSN/GGSN (for EDGE or UMTSpacket traffic); 3G circuit core 213 includes a 3G MSC/VLR; 4G circuitcore 214 includes an evolved packet core (EPC); and in some embodimentsthe Wi-Fi access network may be connected via a 2G circuit core 215 witha 2G MSC/VLR. Each of these nodes are connected via a number ofdifferent protocols and interfaces, as shown, to other, non-“G”-specificnetwork nodes, such as the SCP 221, the SMSC 222, PCRF 223, HLR/HSS 224,Authentication, Authorization, and Accounting server (AAA) 225, and IPMultimedia Subsystem (IMS) 226. An HeMS/AAA 227 is present in some casesfor use by the 3G UTRAN. The diagram is used to indicate schematicallythe basic functions of each network as known to one of skill in the art,and is not intended to be exhaustive. Noteworthy is that the RANs 201,202, 203, 204 rely on specialized core networks 211, 212, 213, 214, 215,but share essential management databases 221, 222, 223, 224, 225, 226.More specifically, for the 2G GERAN, a BSC 201 c is required for Abiscompatibility with BTS 201 b, while for the 3G UTRAN, an RNC 202 c isrequired for Iub compatibility and an FGW 202 d is required for Iuhcompatibility.

FIG. 3 is a schematic network architecture in accordance with someembodiments. The architecture shown is an exemplary “brownfield”deployment architecture, i.e., an architecture being deployed usingexisting equipment and assets, and adds a virtual RNC gateway (VRNCGW)301, which can be a Parallel Wireless HetNet Gateway, or othervirtualizing, coordinating, and base station managing node. 2G RAN(GERAN) 302, with mobile station (MS) 302 a and BTS 302 b, isrepresented, but an Abis interface is made directly between GERAN 302and gateway 301. 3G RAN (UTRAN) 303, with UE 303 a and base station 303b, connects directly to gateway 301 via Iuh or Iub without an RNC, asthe gateway handles the RNC functions. If a nodeB is used, the Iubprotocol may be used; if a home NodeB or femto is used, the Iuh protocolmay be used. 4G RAN (EUTRAN) 304 is represented by UE 304 a and eNodeB304 b, which communicates via S1 to the gateway 301; S1 is theprotocol/interface used for eNodeBs in communicating with the LTE basestation managing node, the MME. A Wi-Fi RAN 305, including Wi-Fi device305 a and AP 305 b, using SWu, is also directly connected to VRNCGW 301,which permits it to be part of the mobile operator network. Instead ofSWu, S2a and S2b may also be used; S2a may be used by/for a trustedwireless access gateway (TWAG), and provides a single IPsec tunnel,while S2b is used for interacting as an evolved packet data gateway(ePDG), which is an untrusted gateway that permits multiple IPsecsessions to be opened.

Gateway 301 handles all protocol communications with the inner corenetwork. It may send 3G sessions to either the 3G packet core 311 or the3G circuit core 312, or 4G sessions to the 4G packet core 313, orcircuit-switched fallback (CSFB) sessions to 3G circuit core 312.Authentication, location registration, or packet-based VoIP etc. ishandled according to the prior art by PCRF 314, AAA 315, SCP 321, SMSC322, HLR/HSS 323, IMS 324 as usual. By the action of the gateway 301 asa virtualizing proxy, extraneous details of the RAN are hidden from thecore network and vice versa. The gateway is also enabled to performsteering or slicing as appropriate, so that certain UEs or base stationscan be directed to other “Gs” (RANs) or resources can be split amongnetworks. The 2G GERAN core network has been eliminated, as all 2Gsessions can be handled by the 3G core. Although the legacy GERANrequires that the gateway 301 use Abis, the core network may view thelegacy 2G MS's as 3G UEs. The VRNC may provide both a virtual RNC and aHNBGW, in some embodiments, thus enabling RAN virtualization andcoordination for both 3G and 4G nodes. The VRNC may also provide avirtual BSC in some embodiments for legacy GERAN base stations.

This architecture has the following advantages and characteristics, insome embodiments. By having the different RANs share a single gatewayand by having UEs/MS's share core networks, less complexity is requiredin the core and operators are not required to keep multiple corenetworks active. A heterogeneous network is enabled to be usedefficiently. As well, although implementation of the gateway 301requires increased complexity, this results in additional potential forfeatures to be added, such as coordination features across RANtechnologies. By terminating connections, lower-layer encryption istypically not in place, allowing for deep packet inspection and lawfulintercept (although application-layer encryption is still potentially inplace).

FIG. 4 is a schematic network architecture in accordance with somefurther embodiments. The architecture shown is an exemplary “greenfield”deployment architecture, i.e., an architecture being deployed with newpurchases of equipment to provide coverage in areas previously notserved by existing equipment. 2G GERAN 402, with MS 402 a, BTS 402 b; 3GUTRAN 403, with UE 403 a and nodeB 403 b; 4G EUTRAN 404, with UE 404 aand eNodeB 404 b; and Wi-Fi access network 405, with mobile device 405 aand AP 405 b, are still present and each continue to go through VRNCGW401. However, in this configuration it is not necessary to provide a 3Gpacket core or circuit core. Instead, a 4G packet core 410 is provided,as well as functions for enabling the 4G core: AAA 411, PCRF 412, HSS413, and IMS nodes P/I/S-CSCF 414, wireless TAS 415, IP-SM-GW 416, andIM-SSF 417. The IMS core provides voice calling functions and the 4Gpacket core provides data calling functions.

VRNCGW 401 enables this core network simplification in conjunction withenhanced base stations in the RAN. Instead of legacy 2G and 3G basestations, Parallel Wireless CWS/BTS 402 b and Parallel WirelessCWS/nodeB 403 b provide additional functionality. CWS/BTS 402 bcommunicates with 2G MS 402 a using an A interface, but instead ofrequiring Abis, CWS 402 b may interwork the A interface and providevoice calling using RTP and SIP via IMS, thus requiring only a standardpacket-switched session that 4G core network 410 can provide. ParallelWireless CWS/nodeB 403 b may interwork CS sessions similarly to IMS.CWS/BTS 402 b and CWS/nodeB 403 b both only require Iuh to be handled byVRNCGW 401, such that the VRNCGW is required only to use Iuh andS1/S2/SWu.

Although not shown, it is apparent that this network architecture isflexible and accommodates a variety of configurations. The generalapproach being used here is to provide a stateful proxy at the gatewaythat is capable of handling a particular protocol/interface. Since thegateway sits at the center of the network for both the RAN (andtherefore the UE or mobile device) and the core network, the statefulproxy can have appropriate knowledge about the messages that have beensent. The stateful proxy can also suppress messages, change headers,insert messages, or perform other proxy functions. A finite statemachine (FSM) may be used for handling state, which may be tracked formobile devices (MS, UE, etc.) or base stations (nodeB, ENB, HENB, Wi-FiAP, etc.) as well as the core network nodes themselves.

In some embodiments, methods for coordinating between base stations arealso available using X2, Iur, and Iurh protocols. The X2 interface isused between 4G eNodeBs. The Iur interface is used between RNCs. Usingthe VRNCGW as a proxy and gateway, the VRNCGW may be able to provideIur-based nodeB coordination with other RNCs, as well as interworkingbetween X2 and Iur for heterogeneous RAT coordination. The VRNCGW mayalso use Iurh interface to exchange coordination information with homenodeBs as a HNBGW. This type of signaling enables features such as softhandover, direct handover, COMP, ICIC, and others. Proxying andaggregation of these interfaces at the VRNCGW has also been considered.

FIG. 5 is a schematic network architecture showing security andsignaling characteristics in accordance with some embodiments. 3G nodeBs501 and 502 are connected via Iuh/Iurh to VRNCGW 503. An enhancedmessaging service (EMS) server 504 is also connected to VRNCGW 503 forproviding text messaging and other services. VRNCGW provides 3Gself-organizing network (SON) capability, HNBGW capability, and securitygateway capability to RANs 501 and 502. RAN 501 is connected over aWi-Fi backhaul link; RAN 502 is connected via a physical link or anotherlink. Both RAN 501 and 502 have opened IPsec tunnels to VRNCGW 503,which terminates the tunnels and decrypts the contents. VRNCGW 503, viaits security gateway (SeGW), then takes the output of the tunnels andsends them via additional IPsec tunnels that connect to, in thisparticular network configuration, an RNC 505 (via Iur for inter-RNCcoordination), an SGSN 507 (via IuPS for delivery of packet traffic),and an MSC 506 (via IuCS for delivery of circuit-switched calls). Thesenodes 505, 506, 507 are in the 3G core network, and no additionalsecurity is needed between these nodes and other nodes in the corenetwork. MSC 506 connects to the regular telephone network, e.g., thePSTN 508, to provide call connectivity. SGSN 507 connects to GGSN 509,which connects to the public Internet 510.

Components

The Parallel Wireless solution may include the following components

Converged Wireless System (CWS)—the CWS component is a multi-technologybase station with an integrated backhaul (wired, microwave, mesh andLTE) that supports LTE, and LTE Advanced, 3G, and Wi-Fi access,simultaneously. The CWS series is available in different form factorssuch as outdoor, in-vehicle small cell, and indoor.

HetNet Gateway—the HetNet Gateway (Parallel Wireless HNG) is acarrier-grade server that is NFV/SDN-based, 3GPP-compliant RANorchestrator that enables RAN hyperconnectivity by unifying anytechnology (3G, 4G, Wi-Fi), any vendor RAN by presenting it as onecommon interface to the core. Parallel Wireless HNG logically sitsbetween the RAN and the core and abstracts the RAN on COTS hardwarewhile making the RAN self-configuring, self-optimizing, andself-healing. To provide hyperconnectivity and to manage the RAN inreal-time, the Parallel Wireless HNG combines these virtualized networkfunctions: virtual-eNB, HeNBGW, X2 gateway, HNBGW/vRNC, ePDG,TWAG/SaMOG, SON server, edge/cell site aggregation, and the securitygateway. It is also an Internet of Things (IoT) enabler, and eIBMSenabler by adding MCE and MBMS-GW functionality and analytics. Itoptimizes the signaling and data traffic going to core network to allowoperators to scale the network to meet growing capacity demands at lowcost. In an LTE network, the HetNet Gateway (Parallel Wireless HNG) nodelogically sits between the eNodeBs and the MNO Evolved Packet Cores(EPCs). It orchestrates thousands of base stations to look like a singleone to the MNO packet core. The Parallel Wireless HNG virtualizes theradio network resources such as eNodeBs and backhaul and makes themself-configurable and self-adjustable. It acts as HeNBGW andvRAN/virtualENB. It allows plug and play operation of CWS nodes and meshbackhaul, and allows them to form an ad hoc network as the nodes come into the network and leave. In a 3G network, the Parallel Wireless HNGprovides the Home Node B Gateway and virtual RNC functionality. ForWi-Fi, the Parallel Wireless HNG acts as a Wireless LAN Controller(WLC), Evolved Packet Data Gateway (ePDG) and Trusted Wireless AccessGateway (TWAG). These are all configurable options and one or the othercan be configured based on an operator's requirements. In someconfigurations Parallel Wireless HNG also acts as an EPC. The HetNetGateway sits between the RAN and the core network, and as a result is ina position to provide proxying and virtualization for any-G and for anycore or multiple cores, as well as being able to perform deep packetinspection and lawful intercept for data flowing through the networkthat would be encrypted if intercepted at a different point in thenetwork.

Uni-Manage—the Uni-Manage software is an Element Management System (EMS)for the CWS and HetNet Gateway (Parallel Wireless HNG) components, andprovides a web-based Graphical User Interface (GUI) for operators tomanage and monitor the network elements.

In some embodiments, a Parallel Wireless CWS may be used to provide 3GRadio Access, providing WCDMA air interface network interfaces for theCWS towards 3G core. When using the CWS, or another small cell or femtonode, it is possible in some embodiments to use the Iuh or Iur protocolto effectively provide 3G configuration and control for those nodes.When providing configuration and control for traditional 3G macro cells,the commonly-used Iub interface is supported by the Parallel WirelessHNG as well, and the Parallel Wireless HNG acts as the RNC for such abase station. In some embodiments, Iub and Iuh may be enabled at thesame gateway. In some embodiments, a lower-level radio L1/L2 layer maybe implemented in a hardware or software module on the Parallel WirelessCWS, or a software state machine for handling L1/L2 messages at theParallel Wireless HNG.

Features of IuGW

In some embodiments, Parallel Wireless HNG may act as or provide an IuGwfunctionality. It may also encompass 3G SON and security gateway. Insome embodiments, CWSes are virtualized by which HNB endpoint (towardsexternal HNBGW) would be configured. There could be multiple CWSesvirtualized per HNB endpoint or it could be a single CWS (macro handover). In some embodiments, Parallel Wireless HNG may register largenumber of UEs (could be in thousands) from one HNB endpoint. HNBGW willbe capable of supporting large number of UEs behind one HNB node. Insome embodiments, a SON module may provide the functionality toprovision CWS with information like Cell-ID, PSC and other OA&M details.SON may provide API to validate CWS attributes at the time of HNBregistration. SON features may be enabled in some embodiments, such as:MRO—Iurh based, Outage Detection & Compensation, Coverage and CapacityOptimization, Energy Savings, Modification of Antenna Tilts, ICIC. Insome embodiments, mobility optimization (a SON feature) may be enabled.In such an embodiment, Parallel Wireless HNG will be acting as Iur &Iurh proxy concentrating handovers. In such configuration handovers willbe performed directly from the MACRO RNC to Parallel Wireless HNGbypassing 3G core network. In some embodiments, IuGw may exposeindividual CWS to HNBGW. So in a deployment scenario, there will be aset of CWSes which are emulated one-to-one with external HNBGW and therewill a set of CWSes which as a group is emulated as one HNB withexternal HNBGW. The CWSes may be grouped in various ways. In someembodiments Parallel Wireless HNG based HNBGW uses CWS grouping tovirtualize resources and allow flexible and auto assignment of LAC/SACetc. In some embodiments Parallel Wireless HNG based HNBGW uses CWSgrouping for RTP localization for a set of CWSs.

In some embodiments, this IuGW provided by the HetNet Gateway may bemore than a simple router or proxy. Instead, the IuGW may handle Iub forcommunicating with 3G macro base stations, Iuh for communicating withHome NodeBs, or both in the same gateway, typically as separate softwaremodules or sharing a state machine for tracking the behavior of the UE.In some embodiments this is done by providing a virtual RNCfunctionality at the base station. The virtual RNC functionality may bea complete software-virtualized RNC, in some embodiments, but may be asoftware state machine-driven proxy, in other embodiments, tracking thestate of the remote nodeB as well as any attached UEs. The virtual RNCmay communicate with other RNCs, virtual or non-virtual, or HNBGWs viaIur, and may communicate to HNBs using Iurh as well. The virtual RNC mayterminate any tunnels needed to provide service to the UE. For example,the VRNC may act as a endpoint for a GTP-U tunnel carrying user data toa SGSN in the core network.

In some embodiments, the IuGw may run as part of Parallel Wireless HNG(LTE Access Controller, the Parallel Wireless controller node); may usethe Parallel Wireless HNG build environment and scripts; Binaries mayget packaged as part of unicloud rpm; may run as part of ‘pwbootd’service; may use UniTask framework for process management; may useParallel Wireless HNG confd CLI for configuration and statisticsmanagement; may use Parallel Wireless HNG alarm framework for alarmgeneration; and may use Parallel Wireless HNG logging framework forlogging and for managing logging level. In some embodiments, Loaddistribution for control plane traffic may be implemented. Control planetraffic concentration towards external 3G core may be implemented. IuGwmay forward user plane packets as UDP proxy using kernel module or dpdk.The IuGw proxy may be extended to full-fledged HNBGW running in ParallelWireless HNG. But it is not expected to run HNBGW and Iuhproxy on thesame Parallel Wireless HNG at the same time.

In some embodiments, deployment model here means that, criteria used forgrouping multiple CWS-HNB's as single HNB, how many such grouping wouldbe made and how are the cell-ids allocated to CWS and how they aremapped on the interface to HNBGW, etc. Group configuration may be usedto associate one or more CWS and one HNB in it. When a message entersthe Parallel Wireless HNG, group name for that message will beidentified and tagged with the message. This group name is used by allprocess to identify required configurations and ingress/egress SCTPconnections, etc. Parallel Wireless HNG need not interface with externalHNB Management System (HMS), in some embodiments.

In some embodiments, an OAM may be included that contains: EMScommunicating with Parallel Wireless HNG using NetConf Interface andpresenting CWS & Parallel Wireless HNG Data Models; HMS Server; aParallel Wireless HNG translation function providing interworkingbetween the ConfD and Iuh provisioning; and SON features.

In some embodiments 3G Radio Access CWS, providing WCDMA air interfaceand Iuh interface towards HNB GW; Parallel Wireless HNG functionality,first phase deployment Parallel Wireless HNG will be playing multiplefunctions: IuGw; 3G SoN; SeGW—Security requirements contain bothrequirements for the IPsec, securing communication between the CWS nodeand the Parallel Wireless HNG where Parallel Wireless HNG is acting asSeGW, CWS WCDMA over the air security; and L2 WiFi Mesh security; OAM,that contains; EMS communicating with Parallel Wireless HNG usingNetConf Interface and presenting CWS & Parallel Wireless HNG DataModels; HMS Server providing TR-069 support; Parallel Wireless HNGtranslation function providing interworking between the ConfD and Iuhprovisioning; SoN features (such as MRO (Inter WCDMA only and statisticsbased), ANR, and PCI Planning & Optimization).

Supported in some embodiments: circuit-switched fallback (CSFB) fromthird party 4G Macro; CSFB from 4G CWS; Intra Frequency Handovers CNanchored; Inter Frequency Handovers CN anchored; Inter RAT HandoversParallel Wireless HNG anchored; Intra Frequency Handovers ParallelWireless HNG anchored; Inter Frequency Handovers Parallel Wireless HNGanchored; Inter RAT Handovers Parallel Wireless HNG anchored. Alsosupported in some embodiments is maintaining the continuity of UEsupport during RNSAP Relocation by transferring the information from theSource HNB to the Target HNB according to the section 5.10 of 3GPP TS25.467 V11.1.0.

RANAP signaling is used to establish the Radio access bearers (RABs) insome embodiments. RAB-Assignment Request of RANAP carries all thedetails of the RABs. This message is usually carried inside the RUADirect-Transfer message (except in the case of relocation).

Additional features in some embodiments include: Aggregation of theIPsec connections from the CWSs towards 3G Core; Aggregation of SCTPConnections from the CWSs towards 3G Core; Virtualization of the 3GNetwork; Radio resource management as RNC; Paging and handoveroptimization for smallcells managed by IuGW; Enable localized services,differentiated QoE for a group of NodeBs such as RTP localization.

Registration

At service start up Parallel Wireless HNG registers all the configuredHNBs with external HNBGW. When CWS does a HNB registration it is locallyprocessed and accepted by Parallel Wireless HNG. When the UE registersfrom CWS, it forwards the UE registration towards HNBGW after replacingrequired IEs. When service starts up, HGWCon performs HNB registrationfor configured HNBs with external HNBGW. When CWS does a HNBregistration HNBCon processes and accepts the registration. When a UEregister message is received at HNBCon, it selects a UEMgr and forwardsit to that instance. HNBCon will tag this message with the group basedon configuration and forward to UEMgr. At UEMgr a new entry for this UEis created and forwards it to HGWCon. At HGWCon it identifies the HNBfor the group name and forwards the UE registration.

Mobility

Mobility between two different CWS Groups. When a UE moves between twodifferent CWS groups external HNBGW needs to be informed. When ParallelWireless HNG receives the ‘Relocation Request’ it maps the CWS ID andCell ID to the corresponding HNB-ID and Cell ID for external HNBGWinterface and forwards it to HNBGW. When it receives response it maps itback to the CWS interface IDs and forwards it to CWS. For all themobility control plane messages Parallel Wireless HNG does the similarmapping and forwards it accordingly.

Internally for the mobility scenario, UEMgr maintains the mobility FSMstates. When HGWCon forwards the message to external HNBGW it replacesthe cell-id with correct cell-id as required for HNBGW interface.Similar call flow will apply for mobility with macro zone. Mobilitybetween two CWS of same group—Node Level Call Flow. When a UE movesbetween CWS of same groups, no need to inform external HNBGW about themovement. Parallel Wireless HNG locally anchors the mobility.

Topology Hiding and Grouping

In some embodiments, the use of a virtualizing gateway may solve theproblem of an increased number of small cells, to provide more capacity,more users, more handovers, and more load on the core. The ParallelWireless HNG virtualizes small cells A, B, C, D to appear only as smallcell A. Suppose RF planning isolates cells B, C, D from macro. Macrohands over to and from cell A. Cells B, C, D hand over to A and to eachother. All handovers to and from B, C, D are advantageously hidden fromthe core. In such embodiments, the topology of the network may be hiddento improve handover performance. For example, a macro base station thatcan cover a large area may be preferable to a scattered set of smallcell base stations when traveling at high speed on a highway, but thesmall cell coverage area may be preferable when moving at walking speed.Hiding certain small cells can result in avoiding unneeded andundesirable handovers.

In some embodiments, grouping of a set of nodes is performed. A proxycan be used to enable small cells to connect to a core network. However,a problem with a simple proxy is that some mobility scenarios requireindividual CWSes (small cells) to be exposed to the core. The examplesof such scenarios are as shown herein. Specifically, when a two-stagehandover is made available as shown herein with some cells constitutinga “rural zone” and some cells constituting a “macro zone,” it isdifficult to proxy all individual cells as a single cell, because someof the “rural” cells are not adjacent to the macro and cannot be proxiedtoward the core as if they were a single cell adjacent to the macro.

The solution to this problem is to provide flexible grouping of cellstoward the core. Some CWSes are emulated 1:1 with the HNBGW. Others areemulated as a virtualized group. This mapping may be configuredstatically or dynamically, such as being allocated from a pool. Each CWShas a unique CGI. Each CWS can be assigned its own location area code(LAC), service area code (SAC), and routing area code (RAC), as definedin, e.g., 3GPP TS 23.003, V9.15.0 hereby incorporated by reference,which are identifying parameters for small cells; however, based on whatis needed, some of these parameters may be shared among CWSes, andmultiple CWS can share one or more of these identifiers via a commonprofile. In some embodiments, multiple vRNCs and RNC IDs may besupported. Allocation of groupings to cells may be performed at acontrol node, such as at the Parallel Wireless HNG or HetNet Gateway.The cells may receive their configuration using X2, NETCONF, or anyother control channel. The cells need only be made aware of their owngrouping. The advantages of this are that certain local actions arethereby enabled by the local nodes, such as base station/HNB and UERegistration and mobility between two different small cell groups, asdescribed herein. In some embodiments, the location of each small cellbase station (CWS) may be tracked. Each CWS's CGI may be mapped tolat/long. Location information can be provided for CWS as CWS has GPS.The Parallel Wireless HNG acts as downstream system using CGI tocross-refer to originating cell. 3GPP location based services (LBS)support for emergency calls may be provided. In some embodiments,geographic location may be used to create groups, which may then be usedto perform targeting of ads, disaster warnings, text messages to allsubscribers, etc. In some embodiments, MBMS functions may be performedon individual groups to provide, e.g., localized broadcast. In someembodiments, backhaul may be managed and optimized on a per-group level.Other optimizations may be performed within groups or subgroups.

To support topology hiding feature, Parallel Wireless HNG may hide theCWS IP addressing/ports towards the 3G core and vice versa. This meansthat the RAB Assignment Request coming in from 3G core will beterminated at Parallel Wireless HNG. Parallel Wireless HNG will storethe parameters of the RAB including the transport layer informationprovided by 3G core. Parallel Wireless HNG will then originate newrequest towards the CWS such that it contains transport layerinformation specific to Parallel Wireless HNG. When the CWS replies withRAB Assignment Response message, Parallel Wireless HNG will again storethe parameters provided by CWS and send a response to the HNBGW that mayinclude Parallel Wireless HNG assigned transport network layerparameters. When the data starts flowing through the Parallel WirelessHNG, it will appropriately proxy the data from one side to the otherside based on the control information of how transport networkparameters were assigned for a given bearer.

Each set of CWS that is represented as one virtualized HNB (akaoperator-network) will be configured with its own ingress user-plane IPaddress and egress user-plane IP address. User plane IP address can besame as control plane IP address because user plane is over UDP whilecontrol plane uses SCTP. However, typically it needs to be ensured thatthis same IP is not used elsewhere in the system (e.g. SON/Configmg linketc) where it can now or in future cause conflicts due to UDP port rangeclash. Note that ingress and egress user-plane IP addresses need to bedifferent. In Phase-1, Parallel Wireless HNG will allow configuration ofonly one user plane IP address at ingress and one at egress. In future,we may allow multiple user-plane IP addresses. For each bearer within anoperator-network, Parallel Wireless HNG will allocate one pair of UDPports. This will be communicated to both the CWS as well as to the 3Gcore in RAB Assignment Request/Response messages. When the peers senddata packets to Parallel Wireless HNG for the given bearer, they will bedestined to this UDP port and the IP address of user-plane ingress oregress. Based on the IP address, Parallel Wireless HNG will be able tofind out the direction and based on the UDP port number, it will be ableto find out the bearer. Mapping information will be available which itwill then use to proxy the packet out with appropriate parameters. Whileallocating UDP port number blocks, Parallel Wireless HNG would leave outthe initial system port range. E.g. The port allocation will start after1024. The first bearer to get created can get the port number 1026(first even port after 1024). If PS user-plane is also running on thesame IP address then GTP is going to use UDP port 2152. So that port maybe left out.

Control Plane and User Plane

Parallel Wireless HNG acts as vRNC/HNBGW. While acting as vRNC itinterfaces with outdoor NodeBs (pico, micro, metro) over Iuh interface.It does radio resource management as a typical RNC because it hasvisibility of all the radio nodes and their resources. It presentsstandard based interfaces towards MSC and packet core such as Iu-CS andIu-PS. The HNBGW serves the purpose of a RNC presenting itself to the CNas a concentrator of HNB connections. The interface between CN and theHNBGW serves the same purpose as the interface between the CN (CoreNetwork) and a RNC. Parallel Wireless HNG also performs 3G SON functionsfor PSC allocation and ANR table management. It also provides plug andplay function for 3G node as well as dynamic RF power adjustment.

HNBGW segregates Control Plane & User Plane traffic for performanceenhancement. User plane is further divided into CS and PS user planetraffic.

User plane. In some embodiments, regarding circuit switched (CS) callsetup and data transfer, HNBGW CS user plane is responsible for relayingRTP packets in uplink and downlink directions. In some embodiments,vRNC/HNBGW supports the transport of signaling and data messages over IUand Iuh interfaces for successful CS call establishment and datatransfer. Mentioned below are the messages supported: Iuh signalingmessages using HNBAP over SCTP: HNB REGISTER REQUEST/ACCEPT/REJECT; HNBDEREGISTRATION; UE REGISTRATION/ACCEPT/REJECT; UE DEREGISTRATION; ERRORINDICATION. Iuh signaling messages using RUA over SCTP CONNECT; DIRECTTRANSFER; CONNECTIONLESS TRANSFER; DISCONNECT; ERROR INDICATION. NASsignaling transfer via RANAP message: INITIAL UE MESSAGE; DIRECTTRANSFER; IU RELEASE REQUEST/COMMAND/COMPLETE; RAB ASSIGNMENTREQUEST/RESPONSE; RAB RELEASE REQUEST; RAB MODIFICATION REQUEST;RELOCATION REQUIRED/COMMAND/FAILURE; RELOCATION REQUEST/REQUESTACK/FAILURE; RELOCATION COMPLETE; RELOCATION DETECT; RELOCATIONCANCEL/ACK; PAGING; COMMON ID; RESET/RESET ACK; RESET RESOURCE/RESOURCEACK; ERROR INDICATION; SECURITY MODE CONTROL. In some embodiments,regarding packet switched (PS) call setup and data transfer, Thesignaling messages mentioned with respect to CS would also be supportedfor PS domain. For data transfer during PS call, HNBGW user plane for PSdomain is responsible for relaying GTP packets in uplink and downlinkdirections.

For the user plane, in some embodiments, Parallel Wireless HNG as IuGWwill support both circuit-switched (CS) data proxy and packet-switched(CS) data proxy modes.

For the CS User Plane, in some embodiments, voice or video stream datawill be encoded inside RTP protocol. RTP will be carried over UDP overIP transport. RTCP may be used but is optional. The receiving entity mayignore incoming RTCP PDUs. RTCP is again carried over UDP over IPtransport. Each transport bearer is identified by the UDP port numberand the IP address (source UDP port, destination UDP port, source IPaddress and destination IP address). Parallel Wireless HNG will need toreserve two consecutive ports per transport bearer (one for RTP andanother for RTCP). Pair of two ports is referred as port number block.For RTP protocol, an even numbered UDP port is used. RTCP uses theconsecutive odd numbered port.

Transport layer information for CS plane in RANAP protocol includes‘transport layer address’ and ‘Iu Transport association’. Transportlayer address contains IP address encoded in NSAP(Network-service-access-point) structure as per RFC 4548.Iu-Transport-Association will contain the UDP port inside the Binding-IDfield. This UDP port will be an even numbered port to be used by RTPprotocol.

Voice/video packets are usually very short (approximately less than 100bytes). For every bearer of every user, sending the small packetsincreases the overall link bandwidth requirement because of overhead(UDP/IP) of transferring each packet. Also for the receiving end, packetrate will become a parameter for its overall capacity. To solve this,3GPP has proposed multiplexing scheme where the 3G core advertises onlyone UDP port (called RTP mux port) to the HNB. HNB then collatesmultiple RTP packets (could be of different users) and forms a biggerpacket (which contain smaller RTP chunks and additional multiplexingheaders). HNBGW receives this bigger packet and it then de-multiplexesthe RTP chunks for processing. Multiplexing is defined only in uplinkdirection. Secondly, it is optional. If the HNB does not supportmultiplexing, it can still keep sending the uplink RTP streams as perthe RAB assignment ports and ignore the RTP mux port. In the firstphase, Parallel Wireless HNG behaving as virtual HNB will ignore the RTPmultiplexing if any offered by the 3G core.

HNBGW may support the transfer of short message services (SMS) betweenUEs, in some embodiments, including: SMS-MT: message sent by the UE;SMS-MO:message sent to the UE.

Control Plane. In some embodiments, the control plan acts as follows.The control plane handles signaling messages and manages the TNL addresstranslation, RTP Port/GTP-U TEID management (Tunnel Endpoint Identifier)and sends the TNL address translation updates to user plane applicationover the propriety interface. The circuit-switched user plane handlesthe TNL address translation updates, create/delete/modify RTP session inboth HNB and CN direction, processes and forwards RTP data packetstowards HNB/CN. The packet-switched user plane handles the TNL addresstranslation updates, create/delete/modify GTP-U tunnel in both HNB/NBand CN direction, processes and forwards GTP-U data packets.

HNBGW supports hand-out and hand-in of on-going calls to/fromneighboring cells, in some embodiments, including CS Handover(relocation of context to/from neighboring cells for on-going voiceconversations) and PS Handover (relocation of context to/fromneighboring cells to on-going data sessions). When UE moves betweenCWSes of same group, location reporting and path switching may beimplemented.

HNBGW provides access control for HNBs/UEs based on white listconfiguration, in some embodiments. White list shall contain IMSI andHNB ID information. When the white list configuration is enabled, onlythose HNBs/UEs included in the list are allowed to access HNBGWresources. On the other hand, when disabled, any HNB/UE is allowed toaccess the HNBGW.

FIG. 5 is a schematic network architecture showing security andsignaling characteristics in accordance with some embodiments.

FIG. 6 is a schematic network architecture showing base station groupingin accordance with some embodiments. VRNCGW 611 sits in the networkbetween the RAN and the core network, which here is a 3G core 612.Several base stations, 601, 602, 603, 604, 605, 606, 607, 608, 609, 610are shown. Base stations 601, 602, 603 are handled separately from basestations 604, 605, 606, 607, 608, 609, 610. This is because basestations 604, 605, 606, 607, 608, 609, 610 are in a “virtual zone” 613,which has been designated as not permitted to perform handins from amacro cell. In a rural small cell deployment, this is to ensure thatmobile devices are not handed in when the result of a handin will be animmediate handout, or worse, a call drop due either to a small coveragearea or a coverage area that is not conducive to handing over to anothercell. The grouping method described with respect to this embodiment isapplicable to both 3G and 4G (LTE), although the base stations shown inFIG. 6 are 3G nodeBs. As shown in the interfaces between VRNCGW 611 and3G core 612, the VRNCGW communicates individually to each base station(here, using Iuh), but does not permit the core to address each of thevirtual zone base stations independently. Rather, all of the virtualzone base stations are treated as a single virtual cell with a specialID. As well, the virtual zone base stations are given a separate RNC IDas well, in some embodiments. In order for a handset or mobile device tobe handed over from a macro to one of the base stations managed by theVRNC, the handset must be handed over first to one of the regular basestations 601, 602, 603, and from there it can be handed over to any cellin the virtual zone. This is shown visually in the next figure and isreferred to as two-stage mobility.

FIG. 7 is a schematic base station deployment topology diagram, inaccordance with some embodiments. Shown is a typical “Rural Deployment”.In this type of deployment CWSs are used mainly for coverageaugmentation (not for the data offload under the overlaying macrocoverage). Current WCDMA release concentrates on “Rural” type ofsolution only. The cell IDs are different than shown in FIG. 6 , but thefigure reflects a similar type of deployment. The grouping methoddescribed with respect to this embodiment is applicable to both 3G and4G (LTE), and either a 3G NodeB or a 4G eNodeB may be consideredwherever a base station is shown in this figure. The method described isuseful for deployment of small cells or for underlay of small cellsunder a macro coverage area.

As shown in FIG. 7 , not all Rural zone CWSs will have overlappingcoverage with the Macro Zone, hence in order to support sessioncontinuity, two-phase mobility may be required as shown in this figureand also in FIG. 10 . Hand-in from Macro to neighboring CWSes (forexample hand-in between RAN A and CWS Cell_Id A. entering Rural zone) isa two-phase handover. HNG may be a VRNCGW or management gateway, and CWSmay be a multi-RAT node, in some embodiments.

Macro zone 701 includes macro 801 a, macro 80 ab, and macro 801 c, eachproviding coverage over a large area of a highway. The macro zone iscreated as a group in the VRNCGW or management gateway.

Rural zone 702 includes base stations 702 a, 702 b, 702 c, 702 d, 702 e,702 f, 702 g in HNG management area 702 x, and base stations 702 h, 702i, 702 j in HNG management area 702 y.

Handovers among the base stations shown in FIG. 7 fall into thefollowing categories: small cell to macro handovers, to or from RuralZone to Macro Zone; inter-small cell handovers within an HNG managementarea; and intra-HNG management area handovers. Each HNG management area702 x, 702 y may appear as a single macro base station to the corenetwork, in some embodiments, such that handovers between 702 x and 702y are handled like regular handovers, with the two HNGs transparentlyidentifying which cell the UE is in using the cell ID. For intra-HNGarea handovers, any notification of the handover may be suppressedtoward the core network, as from the perspective of the core network ahandover between two intra-HNG cells does not result in the UE movingfrom one eNB (or NB) to another eNB (or NB).

For handovers to and from the macro network, the handover zone for,e.g., macro 701 a only impinges on cell 702 a. So the HNG will notpermit a handover from the macro A to cells B, C, D, E, F, or G. This isa function of the coverage area of the cells. Otherwise handovers arehandled normally. Various other rules can be set up so that handoversare permitted under only desirable conditions.

Groupings may be performed in the VRNCGW across G's, in someembodiments. For example, the rural zone may include both 3G and 4Gcells, and handovers between them and a set of 3G macros in a macro zonemay be handled according to the described method. Multiple groups perHNG management area may be used in some embodiments. Groupings may bemade based on RF conditions, topological or geographical conditions,trains or highways or other features of the landscape leading toassumptions about user speed, or neighbor relation tables that relate tothe topology of the graph of the cells' coverage areas, or otherfactors.

Operation and Call Flows

FIG. 8 is a signaling call flow showing a handover of a circuit-switchedsession at a gateway, in accordance with some embodiments. UE 801 hasmoved from a first coverage area to a second coverage area, and attachesto a nodeB (not shown), which is controlled by source VRNC 802. SourceVRNC 802 is a VRNCGW, as described herein, proxying and serving as agateway for the nodeB to the 3G core network. The UE 801 requests to behanded over from its prior cell to this cell, and since this is acircuit-switched session, the relocation request is sent from the nodeBto the source VRNC 802 to the MSC 804 in the core network. The MSC 804then sends a message to target VRNC 803, which is the VRNCGW handlingthe UE's prior cell. Handover proceeds in the same manner as describedby the 3G standard; however, in some embodiments source VRNC 802 andtarget VRNC 803 are both VRNCGWs. In some embodiments source VRNC 802may be handling a nodeB using the Iub interface, and target VRNC 803 maybe handling a Home nodeB or a Parallel Wireless multi-RAT node using theIuh interface, or vice versa. In some embodiments both base stations maybe Iub or Iuh. In some embodiments, Iub and Iuh may be enabled bysoftware or hardware modules at the same VRNCGW. In some embodiments,inter-RAT handovers or steering between 3G and 4G may be enabled byhaving 3G and 4G modules on the same VRNCGW.

FIG. 9 is a signaling call flow showing a handover of a packet-switchedsession at a gateway, in accordance with some embodiments. UE 901 hasmoved from a first coverage area to a second coverage area, and attachesto a nodeB (not shown), which is controlled by source VRNC 902. SourceVRNC 902 is a VRNCGW, as described herein, proxying and serving as agateway for the nodeB to the 3G core network. The UE 901 requests to behanded over from its prior cell to this cell, and since this is apacket-switched session, the relocation request is sent from the nodeBto the source VRNC 902 to the SGSN 904 in the core network. The SGSN 904then sends a message to target VRNC 903, which is the VRNCGW handlingthe UE's prior cell. Handover proceeds in the same manner as describedby the 3G standard; however, in some embodiments source VRNC 902 andtarget VRNC 903 are both VRNCGWs. In some embodiments source VRNC 902may be handling a nodeB using the Iub interface, and target VRNC 903 maybe handling a Home nodeB or a Parallel Wireless multi-RAT node using theIuh interface, or vice versa. In some embodiments both base stations maybe Iub or Iuh. In some embodiments, Iub and Iuh may be enabled bysoftware or hardware modules at the same VRNCGW. In some embodiments,inter-RAT handovers or steering between 3G and 4G may be enabled byhaving 3G and 4G modules on the same VRNCGW.

In some embodiments, the solution may support handins from Macro Zoneaccording to section 5.9.4a of [1] (open access HNBs). For ConnectedMode Inbound Mobility for CSG UEs to CSG HNBs or to Hybrid Cells: seesection 5.9.2a of [1]; for Connected Mode Inbound Mobility for non-CSGUEs to CSG HNBs or to Hybrid Cells, see section 5.9.3a of [1] The handinsolution implementation may be based on Parallel Wireless HNG supportingMacro-to-Femto (M2F) handin using the Fan-out approach for RelocationRequest for pre-Rel-9 UEs (Macro-RNC can't identify target-Cell-id). ForEnhanced Relocation from Open Access and Hybrid CWS (HNBs) to RNC—seesection 5.11.2 of [1]; Enhanced Relocation from RNC to Open Access CWS(HNBs) see section 5.11.2.2 of [1]; Enhanced Relocation from RNC toHybrid CWS (HNBs) see section 5.11.2.3 of [1].

FIG. 10 is a signaling call flow showing a two-phase macro to rural zonemobility scenario, in accordance with some embodiments. In this example,a handover is shown between the Macro Zone (RAN A) and the Rural Zone(CWS Cell id A). The method described and shown in this figure relatesto eNodeBs and LTE as well as to nodeBs and UMTS/3G, and also to anyother “G” radio access technology.

UE 1001 is initially attached to macro nodeB A 1002, which is handled byan RNC in the core network (not shown). Also available are IuGW 1003 (aVRNCGW) and CWS base stations 1004 and 1005. CWS 1004 has cell ID A. CWS1005 has cell ID B. Initially, UE 1001 is attached to macro 1002.However, upon performing measurement reports it becomes apparent thatthe signal of the macro is decreasing, and based on measurement reports,at step 1006 the source RNC (not shown) decides to initiate relocationto target CWS A 1004. Target CWS A 1004 is managed by IuGW 1003, thatis, IuGW 1003 is acting as the RNC for this CWS. The source RNC (notshown) sends a RANP Relocation Request with the identified target cell'scell_id=A. As shown in step 1007, the CWS A allocates resources for theUE, and at step 1008, detects the presence of the UE in its coveragearea. The rest of the handover proceeds normally per the 3G standard.The IuGW/VRNC acts as an RNC toward the source RNC, and also acts as anRNC toward CWS A 1004, to facilitate the handover.

FIG. 11 is a signaling call flow showing an Iuh anchored rural to ruralzone mobility scenario, in accordance with some embodiments. FIG. 11illustrates typical high level handover between the CWSs in the RuralZone (for example from CWS Cell_id A to CWS Cell id B). The methoddescribed and shown in this figure relates to eNodeBs and LTE as well asto nodeBs and UMTS/3G, and also to any other “G” radio accesstechnology.

UE 1101 is initially attached to CWS A 1102, which is managed by IuGW1103, which is a VRNCGW as described herein. Also available is CWS basestation 1104, which is also managed by IuGW 1103. CWS 1102 has cell IDA. CWS 1104 has cell ID B. Initially, UE 1101 is attached to CWS 1102.However, upon performing measurement reports it becomes apparent thatthe signal of the macro is decreasing, and based on measurement reports,CWS 1102 decides to initiate relocation to target CWS B 1104. Asaccording to the standard, the source CWS 1102 sends a RUA DirectTransfer Connect request to the IuGW 1103. The IuGW/VRNC does not needto contact the core network to facilitate the handover, but responds bysimply replying with a RUA Direct Transfer relocation command to CWS1102. Once the handover is completed, with a RANAP Relocation Completemessage, the IuGW 1103 intercepts it and no message is sent to the corenetwork. Further messages to the UE from the core network will bedisambiguated and sent to CWS B. The HNBAP UE Deregister message fromCWS 1102 is also intercepted and silenced, e.g., not sent to the corenetwork.

FIG. 12 is a signaling call flow showing additional aspects of a ruralto rural zone mobility scenario, in accordance with some embodiments.Mobility between two CWS of same group—Internal Message Flow. Since theUE moves between CWS of same group, UEMgr doesn't map the CWS and CellIDs. It maintains the mobility FSM states, but instead of involvingexternal HNBGW it locally anchors the mobility. The FSM states for UEmobility between CWS of same group and different group will be differentand it would need two set of FSM transitions.

CWS-Src 1201, which is a base station, is controlled by an HNG,represented by internal modules HNBCon 1202 and UEMgr 1203. At step1205, a handover is requested to CWS-Dst 1204. At step 1206, the UEmgris aware of the state and determines that no mapping is needed with theHNBGW because the two CWSes are in the same group. At step 1207, UEmgr1203 replies with the relevant information for a RANAP relocationrequest, which is passed along by HnbCon 1208, and an additional RANAPrelocation command is sent at step 1209. Relocation is completed withoutsignaling to the core network.

FIG. 13 is a signaling call flow showing base station registration, inaccordance with some embodiments. CWS-2 1301 and CWS-1 1302 areconnected to HNG 1303, which is a VRNCGW as described herein. CWS-1 isstarted first, step 1304, and as part of initialization requestsidentifiers, e.g., LAC, RAC, SAC, and cell ID from the HNG, step 1305.It receives CellId 0x1234501. Next, CWS-2 is started, at step 1306. Whenit initializes and requests identifiers, at step 1307, it receives adifferent cell ID, CellId 0x1234502, which is used thereafter todistinguish the cell at the HNG.

FIG. 14 is a schematic architecture diagram of an exemplary base stationtogether with an exemplary gateway, in accordance with some embodiments.Exemplary CWS base station 1401 includes LTE protocol modules 1401 b, RFmanager 1401 c, OAM manager 1401 d, and platform manager 1401 e, each ofwhich is managed as part of a baseband processing (BBP) module 1401 a.Additionally, address manager 1401 g, Wi-Fi access and mesh manager 1401h, and Config/SON module 1401 i are part of a general purpose processing(GPP) module 1401 f. A single IPsec secure tunnel 1403, in someembodiments, connects the CWS to the HNG 1402. HNG 1402 includes a HomeNodeB manager 1402 a, core network module/HGWcon 1402 b, UE managers1402 c, SON coordinators 1402 d, config manager 1402 e, Wi-Fi manager1402 f, and IPsec managers 1402 g. The modules are all stateful andshare data with each other. Multiple instances of each module arepresent, each with a connection to a distributed control path 1402 h.

The gateway has the following characteristics: distributed control planeacross multiple cores; distributed data path across multiple cores; nosingle point of failure for control and data processing; throttling tolimit traffic on a core; IP access control lists (ACLs) (static ordynamic or both); dynamic ACLs using an algorithm to detect a source IPsending invalid ISAKMP_INIT.

HNBCon and HGWCon interacts directly without UEMgr for non UE relatedmessages like Reset, Paging, etc. When UE is handed off, mobility FSMstates are maintained by UEMgr. HGWCon would have less intelligenceabout the CWS locations and mapping. It maintains the states of HNBconnection towards HNBGW and in a crude sense acts as a pipe towardsexternal HNBGW. This process may be replaced with a full-fledged HGWprocess in some embodiments. HNBCon will maintain HNB FSM states, UEMgrwill maintain HNB-UE FSM, IU FSM, RAB FSM states and HGWCon willmaintain HNB FSM for HNBGW interface. Neighbor table will be maintainedby SON and it will be used for allocating cell id related information.

RUA Connect Forking

In some embodiments, a PCI conflict may occur when two CWSes have thesame cell ID, in this case shown as Cell_id A. The IuGw may gracefullyhandle the conflict by forking the RUA connect request. This results inboth CWS A's being requested to hand in the UE. However, only the CWSwith coverage in the physical region of the UE will be able tosuccessfully respond to the request, and the other forked RUA connectwill fail without negatively impacting hand-in.

In some embodiments, when a PCI conflict is detected, a handover requestmay be forked. Specifically, the handover request may be sent from thesource cell to all cells known to the source cell that have that PCI.Two or more handover requests, then, may be created. However, only onehandover request will ultimately be met/satisfied, because the receivingcell will determine either that the cell does contain the UE identifiedin the request and return a handover acknowledgement message, or thatthe cell does not contain the UE identified in the request and will failand/or not return a handover acknowledgement message. The handoverrequest may be sent either via X2 or S1, in some embodiments.

In small cell deployments there is a high probability of the PCIreuse—similar to PCI conflict—although PCI conflict normally means smallcells are close and there is a problem with UE sync up. So in case ofthe PCI reuse core network becomes confused on the reported targethandover cell site, as it doesn't know any better than PCI (physicalcell id) reported by UE. One commonly deployed method—network getsGlobal Cell Id (CGI) report from UE and uses global cell id instead ofPCI to resolve ambiguity—CGI is unique. Here a different and alternativemethod is proposed—we fork the handover message to all PCI (in case ofambiguity) and wait for one the CWS (can be third party as well we don'tcare) returning acknowledge. As soon as we get it, we continue with thehandover towards this specific small cell and drop other initiatedhandover sessions.

Further embodiments are contemplated. For example, algorithms fordetermining the intent of a user are contemplated, thereby enabling thenetwork to determine whether hand-in is desired. As another example, analgorithm based on the path vector, OSPF path vector, or determined UEspeed may be used for determining UE motion. As another example,admission priority may be influenced by one or more parameters. Asanother example, hand-in to a small cell may be rejected by immediatelyhanding back to a macro, based on hand-in parameters. As anotherexample, thresholds, such as reporting thresholds, cell selectionthresholds, and handover thresholds, may be monitored and set to reduceundesirable hand-ins. As another example, the control plane for the UEmay be anchored at the macro, while some hand-overs are handledtransparently via the IuGw. As another example, a macro overlay network,wherein a macro cell has coverage co-extensive with the coverage area ofthe small cells, may be configured with different hand-in parameters,such as minimal small cell hand-in. As another example, topology gapsmay be pre-configured to disallow handovers, such that if a networkidentifies the direction of travel of a UE as entering a small cell gapin coverage, handover from the macro is disallowed from certain sourcesmall cells or from the macro. Forking may involve creating more thanone copy, in some embodiments.

FIG. 15 is a signaling call flow showing handin with call connectmessage forking, in accordance with some embodiments. UE 1501 isconnected to macro RAN 1502, which is connected to a core network (notshown), and through IuGW 1503 to CWS Cell A 1504 and CWS Cell A 1505,both of which have the same Cell ID. At step 1506, the source cellinitiates relocation. This results in a RANP Relocation Request beingsent to the IuGW. The IuGW does not know which CWS is being requested,and as a result forks the request by sending a copy of the RUA connectrequest to each of cells 1504 and 1505. At step 1507, the IuGW starts atransfer timer. At step 1508, cell A allocates resources for the UE andat steps 1509 and 1510, the handover proceeds normally. By the operationof the handover and by cell 1504 returning messages, IuGW 1503 becomesaware that the UE is in cell 1504.

RTP Localization

The Real-time Transport Protocol (RTP) is a network protocol fordelivering audio and video over IP networks. RTP is used extensively incommunication and entertainment systems that involve streaming media,such as telephony, video teleconference applications, televisionservices and web-based push-to-talk features. RTP is one of thetechnical foundations of Voice over IP (VoIP), and in this context isoften used in conjunction with a signaling protocol such as the SessionInitiation Protocol (SIP) which establishes connections across thenetwork.

In some embodiments, RTP flows may be directed from one endpoint toanother endpoint within the control of the Parallel Wireless HNG,without requiring a session border controller to identify the need for,and provide, hairpin routing. The problem that exists in some situationsis that 3G calls require a session border controller even when the callis locally terminated. However, by providing this functionality at theedge of the network, the network may achieve better latency and otheradvantages.

The edge of network node may be the CWS or the Parallel WirelessHNG/Parallel Wireless HNG. The Parallel Wireless HNG/Parallel WirelessHNG may perform functions including endpoint lookup of call recipientwithin local area based on phone number; redirection of 3G call audio tocall recipient over RTP within a zone; and call termination. No MSC needbe involved. The call may be packet-switched or circuit-switched. Thecall can be a CSFB call; it may be terminated as CS by the CWS at eitherend of the call. Depending on the location of the edge of network node,this function may be performed within a group, across groups, or withina single CWS. Lawful intercept, 3-way calling, hold, conferencing, etc.may be managed by the Parallel Wireless HNG. The advantages may includelower call establishment latency, (lower call latency?), less load atupstream nodes, higher throughput, reduced backhaul requirements, andimproved voice quality as a result of the above.

FIG. 16 is a schematic network architecture diagram showing RTPlocalization, in accordance with some embodiments. CWS group 1/Virtualaccess network A 1601 is a group of CWSes managed by HNG 1604. CWS Group2/Virtual access network B 1602 is another such group, as is CWS Group3/Virtual access network C 1603. Also provided is 3G core 1605, which isin communication with HNG 1604. The HNG 1604 is an RNCGW and providesIuGW services. The HNG has an RTP localization policy, which is enforcedat the HNG. During CS call setup, the HNG determines the need for RTPlocalization and instructs the CWS by changing IP and port. Complete RTPlocalization 1606 (the CWSes are directed to communicate directlywithout going through the HNG), partial RTP localization 1607 (throughthe HNG), or no RTP localization 1608 (through the core) is detected asa possible condition and enforced at the HNG. Detection may be based onCWS groups, whether the cell ID is the same, whether the target ismanaged by the same HNG, or other factors. Further discussion of RTPlocalization appears below.

FIG. 17 is a schematic diagram of a base station management gateway in aLong Term Evolution (LTE) architecture, in accordance with someembodiments. Base station management server 1701 provides services to,and is coupled to, eNodeB 1 1702 and eNodeB 17 1703, on a RAN side of anetwork (i.e., inside of the gateway). Base station management server1701 provides services to, and is coupled to, MME 1704, macro eNodeB1705, and macro eNodeB 1706, on a core network side of the network(outside of the gateway). Base station management server 1701corresponds to LAC 110, in some embodiments.

Within base station management gateway 1701 are self-organizing network(SON) module 1711, containing neighbor relation table (NRT) 1712 and UEmeasurement report processing module 1713; evolved packet core (EPC)module 1721, containing EPC finite state machine module 1722 and macroeNodeB table 1723; radio access network (RAN) module 1731, containingeNodeB finite state machine module 1732 and eNodeB table 1734; and userequipment (UE) module 1741, containing UE finite state machine module1742 and S1/X2 handover mapping table 1743. Each of modules 1711, 1721,1731, and 1741 are coupled to each other within base station managementgateway 1701, and may execute on one or more shared processors (notshown) coupled with memory (not shown).

In some embodiments, SON module 1711 may perform NRT maintenance, loadinformation processing and fractional frequency reuse (FFR) processing;RAN module 1731 may perform X2 association management with eNodeBs 1702,1703; EPC module 1721 may perform X2 association management with macroeNodeBs 1705, 1706; and UE module may perform X2 handover and S1/X2translation between eNodeBs 1702, 1703 and macro eNodeBs 1705, 1706. Allthe above managers/modules interact with each other to accomplish theassigned functionality.

FIG. 18 is a schematic diagram of a mesh network base station, inaccordance with some embodiments. Mesh network base station 1800 mayinclude processor 1802, processor memory 1804 in communication with theprocessor, baseband processor 1806, and baseband processor memory 1808in communication with the baseband processor. Base station 1800 may alsoinclude first radio transceiver 1810 and second radio transceiver 1812,internal universal serial bus (USB) port 1816, and subscriberinformation module card (SIM card) 1818 coupled to USB port 1814. Insome embodiments, the second radio transceiver 1812 itself may becoupled to USB port 1816, and communications from the baseband processormay be passed through USB port 1816.

A virtualization layer 1830 may also be included for mediatingcommunications with an evolved packet core EPC, specifically includingthe core network EPC (not shown) and local evolved packet core (EPC)module 1820. Local EPC 1820 may be used for authenticating users andperforming other EPC-dependent functions when no backhaul link isavailable. Local EPC 1820 may include local HSS 1822, local MME 1824,local SGW 1826, and local PGW 1828, as well as other modules. Local EPC1820 may incorporate these modules as software modules, processes, orcontainers. Local EPC 1820 may alternatively incorporate these modulesas a small number of monolithic software processes. Virtualization layer1830 and local EPC 1820 may each run on processor 1802 or on anotherprocessor, or may be located within another device.

Processor 1802 and baseband processor 1806 are in communication with oneanother. Processor 1802 may perform routing functions, and may determineif/when a switch in network configuration is needed. Baseband processor1806 may generate and receive radio signals for both radio transceivers1810 and 1812, based on instructions from processor 1802. In someembodiments, processors 1802 and 1806 may be on the same physical logicboard. In other embodiments, they may be on separate logic boards.

The first radio transceiver 1810 may be a radio transceiver capable ofproviding LTE eNodeB functionality, and may be capable of higher powerand multi-channel OFDMA. The second radio transceiver 1812 may be aradio transceiver capable of providing 3GPP WCDMA functionality. Bothtransceivers 1810 and 1812 are capable of receiving and transmitting onone or more bands. In some embodiments, transceiver 1810 may be capableof providing both LTE eNodeB and LTE UE functionality, and transceiver1812 may be capable of UMTS BTS functionality, UMTS UE functionality, orboth. The transceivers may be switched. Transceiver 1810 may be coupledto processor 1802 via a Peripheral Component Interconnect-Express(PCI-E) bus, and/or via a daughtercard. As transceiver 1812 is forproviding LTE UE functionality, in effect emulating a user equipment, itmay be connected via the same or different PCI-E bus, or by a USB bus,and may also be coupled to SIM card 1818.

SIM card 1818 may provide information required for authenticating thesimulated UE to the evolved packet core (EPC). When no access to anoperator EPC is available, local EPC 1820 may be used, or another localEPC on the network may be used. This information may be stored withinthe SIM card, and may include one or more of an international mobileequipment identity (IMEI), international mobile subscriber identity(IMSI), or other parameter needed to identify a UE. Special parametersmay also be stored in the SIM card or provided by the processor duringprocessing to identify to a target eNodeB that device 1800 is not anordinary UE but instead is a special UE for providing backhaul to device1800.

Wired backhaul or wireless backhaul may be used. Wired backhaul may bean Ethernet-based backhaul (including Gigabit Ethernet), or afiber-optic backhaul connection, or a cable-based backhaul connection,in some embodiments. Additionally, wireless backhaul may be provided inaddition to wireless transceivers 1810 and 1812, which may be Wi-Fi802.11a/b/g/n/ac/ad/ah, Bluetooth, ZigBee, microwave (includingline-of-sight microwave), or another wireless backhaul connection. Anyof the wired and wireless connections may be used for either access orbackhaul, according to identified network conditions and needs, and maybe under the control of processor 1802 for reconfiguration.

Other elements and/or modules may also be included, such as a homeeNodeB, a local gateway (LGW), a self-organizing network (SON) module,or another module. Additional radio amplifiers, radio transceiversand/or wired network connections may also be included.

Processor 1802 may identify the appropriate network configuration, andmay perform routing of packets from one network interface to anotheraccordingly. Processor 1802 may use memory 1804, in particular to storea routing table to be used for routing packets. Baseband processor 1806may perform operations to generate the radio frequency signals fortransmission or retransmission by both transceivers 1810 and 1812.Baseband processor 1806 may also perform operations to decode signalsreceived by transceivers 1810 and 1812. Baseband processor 1806 may usememory 1808 to perform these tasks.

RTP Localization

As noted above, when a voice call is established from one mobilesubscriber to another mobile subscriber, even though both the mobilesubscribers are camped on to the same base station or NodeB, thesignaling and RTP messages flow between mobile subscribers and mobileoperators' core networks via base station, radio network controllerusing wired or wireless backhaul system. This causes inefficient use ofa backhaul bandwidth and blocking of various types of resources at radionetwork controllers and core networks causing inefficient use of abackhaul bandwidth and blocking of various types of resources at radionetwork controllers and the mobile operators' core network. As theforegoing illustrates, an approach that would require only the signalingmessages to flow between mobile subscribers and the mobile operators'core network while RTP messages are switched locally at the base stationor NodeB where a calling and called mobile subscribers are camped on tothe same base station or NodeB. The approach would save the backhaulbandwidth by not transmitting RTP packets from the base station or NodeBto the mobile operators' core networks over wired or wireless backhaulsystem.

As the foregoing illustrates, an approach that would allow only thesignaling path from a UE1 and UE2 to the mobile operator's core networkthrough the base station or NodeB, the wired or wireless backhaul systemand the coordinating server or gateway when the UE1 and the UE2 arelatched on the same base station when the voice call between them isinitiated and established. The approach would allow RTP packets to beswitched locally at the base station and saving the backhaul bandwidthby not transmitting RTP packets from the base station to the mobileoperator's core network via the wired or wireless backhaul through thecoordinating server or gateway.

Advantageously, the disclosed technology provides techniques forswitching RTP packets locally at a base station when a calling and acalled user equipment are latched to the same base station. As a result,wired or wireless backhaul bandwidth from the base station to acoordinating server or gateway, and resources at a mobile operator'score network are available for other subscribers or operations.

The following references are hereby incorporated by reference in theirentirety: UTRAN Overall Description—3GPP TS 25.401 V8.2.0 (2008December) [1]; UTRAN Architecture for 3G Home Node B—3GPP TS 25.467V.8.10 (2009 March) [2]; 3GPP TS 29.281 GPRS Tunneling Protocols—UserPlane (GTP-U) [3]; 3GPP TS 29.060 GPRS Tunneling Protocol [4]; 3GPP TS25.413 RANAP Signaling [5]; 3GPP TS 23.003 Numbering, Addressing andIdentification [6]; 3GPP TS 25.468—UTRAN Iuh Interface RANAP UserAdaption (RUA) Signaling [7]; 3GPP TS 25.469—UTRAN Iuh Interface RANAPUser Adaption (HNBAP) Signaling [8]; RFC 3868—Signaling ConnectionControl Part User Adaption Layer (SUA) [9]; 3GPP TR 29.903—FeasibilityStudy on SS7 signaling transport in the core network with SCCP-UserAdaption Layer (SUA) [10]; 3GPP TS 25.304—User Equipment (UE) proceduresin idle mode and procedures for cell reselection in connected mode [11];RFC 1889—RTP: A Transport Protocol for Real-Time Applications [12].

High Level Voice Call—RTP Localization Feature

The Parallel Wireless solution supports RTP localization for the voicecalls between the UE's connected to the same base station (NodeB) or thedifferent base stations (connected to each other using Satellite Mesh)managed by the same coordinating server. The coordinating server hassignaling and RTP visibility for every voice call. If this feature isconfigured on the coordinating server and it determines that the voicecall is between the UE's connected to the same base station, it willinstruct the base station to handle the RTP traffic locally between theUE's and not to send the RTP traffic to the MSC or a core network. Thesignaling for the voice call will continue to be handled by the MSC.

In a RTP localized call with two UE's camped on to the same base stationand managed by a coordinating server, the coordinating server may employthe following methods to provide RTP localization feature. Thecoordinating server or a virtualizing server 1701 shown in FIG. 17 mayalso include RTP Localization module to provide RTP localization featureat a base station or a mesh network base station 1800 shown in FIG. 18supports multi-RAT including 2G/3G/4G/Wi-Fi/LTE.

Call Correlation

Call correlation within same cell id.

Coordinating server has to identify the origination and termination legfor the call to be able to handle the RTP traffic locally. The defaultGSM Setup message does not have any unique identifier across the calllegs. With this limitation, a possible approach for call correlation isdiscussed below. In some embodiments, a unique identifier, callcorrelation-id, can be used so that when the call correlation-id sent tothe core network, if the same call correlation-id is retrieved from anetwork setup message from the core network, the coordinating server canassociate the originating and terminating leg of the call. The uniqueidentifier may be generated using any combination of calling partyaddress, called party address, called or calling party IMSI or otheridentifier, date and timestamp of the call origination, base stationradio access network (RAN) identifier etc. The unique identifier may bea random or arbitrary value.

Call Leg Correlation Using User-User IE

In some embodiments, a call correlation id may be generated at thecoordinating server using the information from the originating leg.Based on the presence of the ID in the message from a core network, theoriginating and terminating leg can be identified. The ID generated maybe encoded in the User-User IE in the setup message. The purpose of theuser-user information element is to convey information between themobile station and the remote user. This may be used to pass thecorrelation ID across the call legs. This ID may be removed whileforwarding the message towards UE.

An MSC can support sending the User-User IE unchanged in the CC setupmessage in the terminating leg. In the case where the MSC does notsupport User-User IE in the CC setup message, the MSC can be configuredto bypass checking user services so that the User-User IE can be sentfrom the originating leg to the terminating leg over the core network.

Call Leg Correlation Using IMSI-MSISDN Mapping

Call correlation can also be achieved using IMSI and MSISDN association,in some embodiments. When a UE registers with the coordinating server,the coordinating server upon successful registration may create anassociation between IMSI of the registered UE and MSISDN of theregistered user. The IMSI identifies the base station the user is campedon currently, while MSISDN is used during mobile originated and mobileterminated call setup. The coordinating server may query a provisioningserver or a HLR in the core network to get the MSISDN information, insome embodiments.

Call Leg Correlation Using RTP Dynamic Payload

Call correlation can also be achieved using a dynamic payload RTPpayload type, in some embodiments. The call correlation-id between theoriginating and terminating leg can be exchanged using CSRC list in theRTP header. CSRC list identifies the contributing sources for thepayload contained in the packet and SSRC identifies all sources thatwere mixed together create a packet and allows the correct sourceindication at the receiver. After the call is connected, thecoordinating server may add CSRC in the RTP packet to the core network.When the coordinating server receives the RTP packet back from the corenetwork for the terminating leg, based on the CSRC value, thecoordinating server may determine that an originating and a terminatingbase station for this voice call is same and RTP streams needs to beswitched locally. The coordinating server therefore initiates RABModification procedure as described below.

Further Details

The comfort noise generated at the coordinating server can be using adifferent SSRC, in some embodiments. This should not cause a problem atthe MSC, as the MSC should be capable of processing audio with multipleSSRC streams.

Jitter Buffer Management can be added to base station, in someembodiments. If the RTP frames with multiple SSRC is presented to basestation, it will be able to play the RTP stream.

There may be a loss of initial RTP Payload during enabling and disablingRTP Localization, which may be mitigated using queuing or buffering atone or more network in the system, in some embodiments.

RAB Modification

In certain scenarios, RAB modification may be needed for a RTP localizedcall. RAB modification may be initiated from a core network for theoriginating leg by sending RAB assignment request to a base station in aRTP localized call from a core network (CN) through the coordinatingserver. Exchange of transport network layer (TNL) address for RTP portrequires RAB assignment request from the core network contains a CN IPand port; and the response message received at the coordinating serverfrom the base station contains base station's IP and port number. Thecoordinating server sends its own IP and port to the CN and the basestation.

Similarly, for a terminating leg, RAB modification process may beimplemented as described above.

A node in the network where RTP localization can be performed is notlimited to the base station only. RTP stream can be switched at thecoordinating server as well once the origination and terminating legsare identified. This enables RTP localization for a plurality of basestations that, for example, are connected to a shared backhaulconnection, such as a satellite-backhauled installation of base stationsin a remote area.

RTP localization may be implemented with switching RTP streams or usinga RTP Proxy. The RTP proxy may be located at a base station, or at thecoordinating server, in some embodiments.

UE Mobility

When a UE in a RTP localized call moves to a different base stationmanaged by a different coordinating server causing handover, or handoutto a Macro, coordinating server, or HNBGW, RTP localization function maybe terminated or revoked, in some embodiments. Similarly, in a hand-incase from Macro/coordinating server/HNBGW, RTP localizationfunctionality may not be enabled after UE hand-in for the current call.New calls after hand-in may be provided RTP localization in accordancewith various policies.

Alternatively, RTP localization may be continued across base stations,etc. if backhaul-advantaged transport is available (i.e., if transportof RTP packets between base stations is possible without loading ashared backhaul connection).

Supplementary Services

In some embodiments, supplementary services may be supported with RTPlocalization. For call-related supplementary service procedures duringthe active state of a call, such as call hold and multiparty calls, theFACILITY message is used for the exchange of the Facility informationelements. The RTP Localization function may be revoked for call relatedsupplementary procedures. It may not be applicable for all supplementaryservices like—Call Forwarding, Line Identification etc.

Call Hold

First an active call is setup between two UEs (UE1 & UE2) in the samebase station BS-1. Now for the active call UE1 is trying to place thecall on hold. HOLD, HOLD Acknowledge messages are exchanged between UE1and a core network. Now UE2 is notified about the call hold status usinga FACILITY message. The FACILITY message contains the status as CallHold.

Once the call is put on hold, in some embodiments, the coordinatingserver may update the base station about the transport layer changeusing the Transport Network Layer (TNL) Update Request. As mentionedearlier, this message is typically meant to update TNL information froma base station to a coordinating server. Here the update is sent fromcoordinating server.

In some embodiments, after TNL Update, the base station BS-1 may be ableto process the new RTP stream from the core network (with differentsynchronization source, or SSRC, and sequence number space). After thispoint RTP Localization is no longer applied.

Retrieve function is invoked later for the call on hold. RETRIEVEmessage is sent from the base station BS-1 to MSC via coordinatingserver. After the Retrieve message is successful, RETRIEVE ACK Messageis sent from MSC. If any supplementary services are invoked, the RTPLocalization function will not be applied again, in some embodiments.

Multiparty Call

UE1 & UE2 are registered with base station BS-1 initially. Call from UE1to UE2 is setup with RTP Localization function applied (within the samebase station BS-1). For adding multiparty conference, call from UE1 toUE2 is put on hold. For call hold, the RTP Localization function can berevoked, in some embodiments. Further signaling of multiparty callhappens as usual. For any NAS CC messages which modify the call state,the RTP Localization function can be revoked, in some embodiments.

Lawful Intercept (LI)

Telecommunications interception laws require the capability ofintercepting a mobile user based on the MSISDN number of the subscriber.This is supported by existing Operator mobile core for all calls thatare not locally or mesh switched. Various options are provided forlawful intercept in conjunction with RTP localization, in someembodiments.

In some embodiments, in case a Lawful Intercept is configured for asubscriber on the coordinating server, it may instruct the base stationnot to handle the RTP traffic locally for this subscriber, so that allthe RTP traffic goes to the MSC. The MSC on receiving this trafficshould be able to duplicate the streams towards the LI server.

In some embodiments, the coordinating server can support the SOAP/XMLinterface towards the mediation server or an Operator LI platform. Thiswill be used to enable/disable a lawful intercept for a particularsubscriber. Communications between the coordinating server and OperatorLI platform (LI Server) can be based on TCP/IP messages.

The following two methods will be implemented in the coordinating serverto support lawful intercept for local and mesh switched calls based onTCP Message from the Operator LI platform. All messages will beresponded by the coordinating server.

Cell Level Interception

In some embodiments, upon receiving the Cell Level Interception messagefrom Operator LI platform, coordinating server may disable the RTPlocalization feature for a call originated and/or terminated at a basestation identified by Cell ID parameter.

The message received at the coordinating server may include followingfields.

Message Type: Cell Interception

Message Id: Sequence ID for the message in the format YYYYMMDDxxxxxxxxwhere YYYYMMDD indicates the date of the message and xxxxxxxx indicatesthe decimal sequence ID of the message for the date starting from00000000 and resets to 00000000 at the start of a new date. The messageID may further include a timezone information.

LI State: LI State value “ON” indicates to activate lawful interceptwhile value “OFF” may indicate lawful intercept is deactivated.

Cell-Id: This field identifies the base station for which the lawfulintercept is activated.

Response to Cell Interception message may include following fields.

Response Status: Response status value 1 may indicate success whilevalue 2 may indicate an error. The person skilled in the art mayrecognize that the values chosen to represent successful or failedlawful interception here is for example purpose only.

Message Id: This field identifies the request message from LI server inresponse to which this message is being sent.

The response may further include additional fields in the case of failedlawful intercept activation. One such additional field may be an ErrorMessage field providing reason for the failure. Sample values for thisfield may be “Syntax Error,” “Invalid Base Station Id,” “ResourceUnavailable” etc.

Subscriber Level Interception

In some embodiments, upon receiving the Subscriber Level Interceptionmessage from Operator LI platform, coordinating server may disable theRTP localization feature for a subscriber identified by combination ofsource/destination IP addresses and/or source/destination port numbers.

The message received at the coordinating server for Subscriber LevelInterception may include following fields.

Message Type: UE Interception

Message Id: Sequence ID for the message in the format YYYYMMDDxxxxxxxxwhere YYYYMMDD indicates the date of the message and xxxxxxxx indicatesthe decimal sequence ID of the message for the date starting from00000000 and resets to 00000000 at the start of a new date. The messageID may further include a time zone information.

LI State: LI State value “ON” indicates to activate lawful interceptwhile value “OFF” may indicate lawful intercept is deactivated.

Source IP: This field identifies source IPv4 or IPv6 address of theunder-surveillance UE's voice call stream.

Destination IP: This field identifies the destination IPv4 or IPv6address of under-surveillance UE's voice call stream.

Source Port: This field identifies source UDP or TCP port ofunder-surveillance UE's voice call stream.

Destination Port: This field identifies the destination UDP or TCP portof under-surveillance UE's voice call stream.

Response to Subscriber Level Interception message may include followingfields.

Response Status: Response status value 1 may indicate success whilevalue 2 may indicate an error.

The person skilled in the art may recognize that the values chosen torepresent successful or failed lawful interception or activating ordeactivating base station level or subscriber level lawful interceptionis for example purpose only.

Message Id: This field identifies the request message from LI server inresponse to which this message is being sent.

The response may further include additional fields in the case of failedlawful intercept activation. One such additional field may be an ErrorMessage field providing reason for the failure. Sample values for thisfield may be “Syntax Error,” “Source IP Address not active,”“Destination IP Address not active,” “Source Port not active,”“Destination port not active,” “Resource Unavailable” etc.

Additional embodiments providing additional lawful interceptfunctionality are described below with respect to, e.g., FIG. 20 .

Base Station Grouping

In addition to RTP localization between users of the same base station,this feature allows RTP localization between a group of base stations. Anumber of base stations (maximum of 3) can be configured as part of alogical group and localize RTP for calls between them.

FIG. 19 illustrates the prior art deployment and signaling and RTP pathin a 3G UMTS deployment. As shown, a UE1 1901 and a UE2 1902 areprovided wireless connectivity via a base station 1903. The base station1903 may be also be known as a NodeB, a femto cell, a small cell etc.The base station 1903 from Parallel Wireless is a multi-RAT base stationwith LTE, Wi-Fi, 2G, 3G and 4G technologies that provides a flexibleoutdoor and in-vehicle solution in conjunction with a coordinatingserver 1904 from Parallel Wireless. The coordinating server 1904 mayalso be known and referred as a gateway, a virtualization server in thisdisclosure. The base station 1903 may be connected to the coordinatingserver 1904 over a wired or wireless backhaul system 1907 and 1908. Thebackhaul system 1907 and 1908 may further be a mesh backhaul system. Thecoordinating server 1904 can orchestrate and manage the Radio AccessNetwork (RAN) across multiple technologies, including 2G, 3G, 4G, LTEand Wi-Fi, with high ease of use. The coordinating server 1904virtualizes the RAN interfaces to manage the 2G, 3G and 4G (Long TermEvolution, or LTE, and universal mobile telecommunications system, orUMTS) RANs (HomeNodeBs/NodeBs and eNodeBs/HeNodeBs) in real-time viamulti-technology self-organizing network (SON) and gateway functionalitywhile abstracting RAN changes from the core network and the core networkitself from the RAN.

The coordinating server 1904 acts like a virtual radio networkcontroller (vRNC or virtual RNC) for multi-RAT network handlingresources for different technologies 3G, LTE/4G and WiFi whileoptimizing call processing towards radio and core network elements suchas a mobile switching center (MSC) 1905, a serving global packet radiosystem (GPRS) support node (SGSN) 1906. A gateway GPRS support node(GGSN) 1906 may be co-located at the SGSN 1906. The other elements ofthe core network specifically for an evolved packet core (EPC) for 4Gmay include a home subscriber server (HSS), and a policy charging andrules function (PCRF). The MSC 1905 and a visitor location register(VLR) are the elements of circuit switched (CS) domain of the 3G corenetwork system whereas the SGSN 1906 and the GSGN 1906 are the elementsof packet switched (PS) domain of the 3G core network system. The otherelements of the core network may be a provisioning gateway 1909. Theprovisioning gateway 1909 may be further in communication with a HLR, orthe provisioning gateway may also perform HLR functionality. Thecoordinating server 1904 may be a standalone coordinating server or maybe one of the coordinating server in a load sharing or active-standbymode.

In a 3G UMTS system as shown in FIG. 19 , the UE1 1901 and the UE2 1902are registered with the coordinating server 1904 and latched to the basestation 1903. The base station 1903 may also be referred as NodeB 1903in this disclosure. When the UE1 1901 is attempts to make a voice callwith the UE2 1902 also registered to the coordinating server 1904 andlatched to the base station 1903, dedicated path to carry signaling andRTP traffic messages between the UE1 1901 and the UE2 1902 isestablished. The path to carry signaling messages is established betweenthe UE1 1901 and the base station 1903, the base station 1903 and thecoordinating server 1904 over the wired or wireless backhaul system 1907and 1908, the coordinating server 1904 and the MSC 1905 in the mobileoperator's core network. Further, dedicated path to carry signalingmessages is also reserved between the MSC 1905 and the coordinatingserver 1904, the coordinating server 1904 and the base station 1903 overthe wired or wireless backhaul system 1907 and 1908, and the basestation 1903 and the UE2 1902. Similarly, RTP traffic path is reservedand established between the UE1 1901 and the base station 1903, the basestation 1903 and the coordinating server 1904 over the wired or wirelessbackhaul system 1907 and 1908, the coordinating server 1904 and the MSC1905 in the mobile operator's core network. Further, RTP traffic pathcarrying voice traffic is also reserved between the MSC 1905 in themobile operator's core network and the coordinating server 1904, thecoordinating server 1904 and the base station 1903 over the wired orwireless backhaul system 1907 and 1908, and the base station 1903 andthe UE2 1902. This as described above is a problem because the usefulbackhaul bandwidth is now used for RTP packets carrying voice databetween the UE1 1901 and the UE2 1902, both are registered at thecoordinating server 1904 and are latched to the base station 1903 forwireless connectivity to the mobile operator's core network. The RTPtraffic path may be routed based on various factors, as describedherein, in some embodiments. The RTP traffic path may be provided withimproved QoS, in some embodiments.

FIG. 20 illustrates 3G UMTS deployment and signaling and RTP flow path,in accordance with some embodiments. FIG. 20 shows RTP packets carryingaudio data between a UE1 2001 and a UE2 2002 registered to acoordinating server 2004 and latched to a base station 2003 are switchedlocally at the base station 2003 when the coordinating server 2004determines that the UE1 2001 and the UE2 2002 are both latched to thesame base station 2003.

In some embodiments, a UE1 2001 and a UE2 2002 are provided wirelessconnectivity via a base station 2003. The base station 2003 may beconnected to the coordinating server 2004 over a wired or wirelessbackhaul system 2007 and 2008. The backhaul system may further be a meshbackhaul system. The coordinating server 2004 can orchestrate and managethe Radio Access Network (RAN) across multiple technologies, including3G, 4G and Wi-Fi, with high ease of use. The coordinating server 2004virtualizes the RAN interfaces to manage the 2G, 3G and 4G (Long TermEvolution, or LTE, and universal mobile telecommunications system, orUMTS) RANs (HomeNodeBs/NodeBs and eNodeBs/HeNodeBs) in real-time viamulti-technology self-organizing network (SON) and gateway functionalitywhile abstracting RAN changes from the core network and the core networkitself from the RAN.

In some embodiments, the coordinating server 2004 acts like a virtualradio network controller (vRNC or virtual RNC) for multi-RAT networkhandling resources for different technologies 3G, LTE/4G and WiFi whileoptimizing call processing towards radio and core network elements suchas a mobile switching center (MSC) 2005, a serving global packet radiosystem (GPRS) support node (SGSN) 2006. A gateway GPRS support node(GGSN) 2006 may be co-located at the SGSN 2006. The other elements ofthe core network specifically for an evolved packet core (EPC) for 4Gmay include a home subscriber server (HSS), and a policy charging andrules function (PCRF). The MSC 2005 and a visitor location register(VLR) are the elements of circuit switched (CS) domain of the 3G corenetwork system whereas SGSN 2006 and GSGN 2006 are the elements ofpacket switched (PS) domain of the 3G core network system. The otherelements of the core network may be a provisioning gateway 2009. Theprovisioning gateway 2009 may be further in communication with a HLR, orthe provisioning gateway may also perform HLR functionality. Thecoordinating server 2004 may be a standalone coordinating server or maybe one of the coordinating server in a load sharing or active-standbymode. The coordinating server 2004 is also in communication with LIserver 2011 in the core network and receives instructions regardinglawful intercept activation and deactivation from LI server 2011.

In some embodiments, the UE1 2001 is registered to the coordinatinggateway 2004 through the base station 2003 and attempts to establish avoice call with the UE2 2002 where the UE2 2002 is also registered tothe coordinating server 2004 through the base station 2003. As shown,dedicated path to carry signaling and RTP traffic messages between theUE1 2001 and the UE2 2002 is established. The path to carry signalingmessages is established between the UE1 2001 and the base station 2003,the base station 2003 and the coordinating server 2004 over the wired orwireless backhaul system 2007 and 2008, the coordinating server 2004 andthe MSC 2005 in the mobile operator's core network. Further, dedicatedpath to carry signaling messages is also reserved between the MSC 2005and the coordinating server 2004, the coordinating server 2004 and thebase station 2003 over the wired or wireless backhaul system 2007 and2008, and the base station 2003 and the UE2 2002. Similarly, RTP trafficpath is required only between the UE1 2001 and the base station 2003,and the base station 2003 and the UE2 2002. The bandwidth of thebackhaul system 2007 and 2008 from the base station 2003 to thecoordinating server 2004 and between the coordinating server 2004 andthe MSC 205 at the mobile operator's core network is now available forother operations.

FIG. 21 illustrates a call flow ladder diagram when a voice call isinitiated by a mobile subscriber to another mobile subscriber where boththe mobile subscribers are latched to the same base station, inaccordance with some embodiments. FIG. 21 specifically depicts messagesexchanged while establishing an originating leg of the call.

See TABLE 1 below for the logical steps to perform the operation inaccordance with some embodiments.

TABLE 1 1 UE1 & UE2 Registration with coordinating server 2 Setuprequest sent from UE1 to coordinating server 3 Processing atcoordinating server Decode NAS Generate Call correlation-id Encode inUser-User IE in NAS Message 4 Authentication and security procedure isexecuted. After Authentication is successful, RAB establishment happensfor originating leg. At this point base station shall be prepared toprocess any IuUP pdus from MSC (Ring back tones etc). 5 IuUPInitialization procedure is invoked as a result of RAB establishment. 6After IuUP initialization is done, IuUp data PDUs can be sent by MSC 7Further steps in processing the setup request. To reach the UE2, pagingrequest is sent and the setup is forwarded 8 To identify the terminatingleg, processing at coordinating server involves Decode NAS to getcorrelation-id Look up the RTP Local call using call correlation-id Linkoriginating and terminating legs 9 Setup Message is forwarded to UEthrough base station 10 RAB Assignment for terminating leg. Here tooafter RAB Assignment is complete, base station shall be able to processany RTP packets from MSC. 11 IuUP Initialization procedure is invoked asa result of RAB establishment for the terminating leg. 12 After IuUPinitialization is done, IuUp data PDUs can be sent by MSC 13 After RABassignment is complete, a proprietary message Transport Network Layer(TNL) Update message is sent from coordinating server to base station toupdate the RAB transport layer parameters for UE1. The IP/Port will bethe one used for UE2 at base station. After the RAB Resources areupdated, TNL Update Response is sent from base station. 14 TNL UpdateRequest/Response message is exchanged for UE2 context 15 DTCH Audioframes generated by UE1 & UE2 are switched locally within base station16 Coordinating server will generate comfort noise for the RABsestablished towards the core network (CN) to avoid Iu Release 17 Calldisconnect & Iu release procedures.

In some embodiments, as shown in FIG. 21 , a UE1 2101 and a UE2 2102 areregistered to a coordinating server 2104. The UE1 2101 and the UE2 2102performs registration procedure. The user equipment (UE) may also bereferred by many other names such as mobile device, a phone etc. Theladder call flow diagram shown in FIG. 21 describes various messagesexchanged between the UE1 2101, the UE2 2102, a base station 2103, thecoordinating server 2104 and a MSC 2105. The base station 2103 may alsobe known by many other names such as a NodeB, a femto cell, a microcell, a pico cell etc.

In some embodiments, to originate a new call, the UE1 2101 initiatesService Request for a mobile originated call. The UE1 2101 sends a radioresource control (RRC) Initial UE carrying a non-access stratum (NAS) CMService Request as a payload to the base station 2103. The base station2103 upon receiving RRC Initial UE/CM Service Request message builds andsends to the coordinating server 2104 a radio access network applicationpart (RANAP) user adaption (RUA) Connect message that encapsulates a NASCM Service Request as a payload. The RANAP Connect message triggers Iuconnection establishment between the base station 2103 and thecoordinating server 2104. The RANAP Connect message carries radio areanetwork (RAN) identification (ID) of the base station 2103. Thecoordinating server 2104 sends SCCP ConnReq carrying RANAP Initial UEMessage to the MSC 2105 of a mobile operator's core network. The MSC2105 accepts and sends positive acknowledgement via SCCP ConnectionConfirm to the coordinating server 2104.

The UE1 2101 sends a setup request via RRC Direct Transfer with NASSetup as a payload to the base station 2103. The base station forwardsRANAP Direct Transfer carrying NAS Setup over RUA to the coordinatingserver 2104. The coordinating server 2104 decodes the received NAS Setupmessage looking for a called party information and creates a callcorrelation-id. The call correlation-id is then encoded as a User-UserInformation Element (IE) in a NAS message that will be sent by thecoordinating server 2104 to the MSC 2105 as a Signaling ConnectionControl Protocol (SCCP) message. The SCCP message from the coordinatingserver 2104 to the MSC 2105 carries the NAS message with User-User IE.The MSC 2105 initiates and completes authentication and securityprocedure verifying the call origination service for the UE1 2101.

After successful authentication and execution of security procedure,radio access bearer establishment and call setup procedure completed.The MSC 2105 sends RANAP RAB Assignment Request message over SCCP to thecoordinating server 2104. Upon determining that the UE1 2101 isauthorized for the requested originating call service, Iu bearerconnection is established by the base station 2103 when the coordinatingserver 2104 forwards the received RANAP RAB Assignment Request messagefrom the MSC 2105. The base station 2103 sends IuUP Init message to thecoordinating server 2104 and the coordinating server 2104 forwards thesame to the MSC 2105. The MSC 2105 acknowledges the establishment ofbearer assignment by sending IuUP Init Ack message to the coordinatingserver 2104 and the coordinating server 2104 further sends IuUP Init Ackmessage to the base station 2103. At this point, the base station 2103is prepared to process any IuUP PDUs from the MSC 2105. The IuUP PDUsmay be for example ringback tones, announcements etc. The base station2103 sends RANAP RAB Assignment Response message to the MSC 2105 throughthe coordinating server 2104.

FIG. 22 illustrates a call flow ladder diagram when a voice call isinitiated by a mobile subscriber to another mobile subscriber where boththe mobile subscribers are latched to the same base station, inaccordance with some embodiments. FIG. 22 specifically depicts messagesexchanged while establishing terminating leg of the call.

In some embodiments, a UE2 2202 is registered to a coordinating server2204 through a base station 2203. The UE2 2202 is the same UE2 shown inFIG. 21 as the UE2 2102. The base station 2203 is the same base stationshown and described in FIG. 3 the base station 2103. The coordinatingserver 2204 is the same coordinating server as shown in FIG. 21 anddescribed before as the coordinating server 2104. A MSC 2205 is the sameMSC as shown and described before as the MSC 2105.

The MSC 2205 while further processing the received NAS Setup from thecoordinating server 2204 sends paging request to the coordinating server2204. The coordinating server 2204 broadcasts the paging requestaccording to various algorithms for efficient paging, and the basestation 2203 where the UE2 2202 is camped on currently, establishes RRCConnection Setup with the UE2 2202. Upon successful RRC connection setupestablished, and successful authentication and security procedure, thebase station 2203 sends paging response to the coordinating server 2204.The coordinating server 2204 sends SCCP Connection Request carryingPaging Response to the MSC 2205. The MSC 2205 sends a SETUP message as aNAS payload in a RANAP Direct Transfer message to the coordinatingserver 2204. The coordinating server 2204, upon receipt of the RANAPDirect Transfer message carrying NAS SETUP message, decodes the NASmessage and extracts the correlation id. The coordinating server 2204further links the originating and terminating legs of the call based onthe correlation ID if the extracted call correlation-id is one which wasencoded by the coordinating server 2204 in User-User IE. Thecoordinating server 2204 then sends the SETUP message to the UE2 2202through the base station 2203. The MSC 2205 sends RANAP RAB AssignmentRequest message over SCCP to the coordinating server 2204. Iu bearerconnection is established by the base station 2203 when the coordinating2204 forwards the received RANAP RAB Assignment Request message from theMSC 2205. The base station 2203 sends IuUP Init message to thecoordinating server 2204 and the coordinating server 2204 forwards thesame to the MSC 2205. The MSC 2205 acknowledges the establishment ofbearer assignment by sending IuUP Init Ack message to the coordinatingserver 2204 and the coordinating server 2204 further sends IuUP Init Ackmessage to the base station 2203. At this point, the base station 2203is prepared to process any IuUP PDUs from the MSC 2205.

FIG. 23 illustrates a call flow ladder diagram when a voice call isinitiated by a mobile subscriber to another mobile subscriber where boththe mobile subscribers are latched to the same base station, inaccordance with some embodiments. FIG. 23 specifically depicts messagesto instruct a base station to switch RTP packets locally when acoordinating server determines that a UE1 and a UE2 are camped on thesame base station.

In some embodiments, messages exchanged between a coordinating server2304, which is also identified earlier as the coordinating server 2204and the coordinating server 2104, and a base station 2303, which is alsoshown earlier as the base station 2203 and the base station 2103, isshown. The coordinating server 2304 identifies and links the originatingand terminating leg of the call based on a call correlation-id. Afterlinking the originating and the terminating call, if the coordinatingserver 2304 determines bases on NAS messages received for theoriginating and the terminating leg that the originating and terminatingleg of the call i.e. a UE1 2301, which is earlier described as the UE12201 and the UE1 2101, and a UE2 2302, which is earlier described as theUE2 2202 and the UE2 2102, are camped on the same base station 2303, thecoordinating server 2304 activates RTP localization feature and sends aRAB Assignment Request to the base station 2303 with a RAB Modify Listfor the UE1 2301 and the UE2 2302. The coordinating server 2304 may berequired to be configured for RTP localization feature or it may be adefault behavior at the coordinating server 2304. If the RTPlocalization feature is provisioned and is active for the base station2303, the RAB Assignment Request sent to the base station 2303 for theUE1 2301 includes an IP address of the base station 2303 and a RTP portNumber assigned for UE2 2302 to update RAB transport layer parameters atthe base station 2303. The RAB Assignment Request sent to the basestation 2303 for the UE2 2302 includes an IP address of the base station2303 and a RTP port Number assigned for UE1 2301 to update RAB transportlayer parameters at the base station 2303. As a result of this RABmodification, RTP packets from the UE1 2301 and the UE2 2302 areswitched locally at the base station 2303. The coordinating server 2304generates and sends comfort noise RTP packets to the MSC 2305 in a corenetwork to avoid Iu Release. Because of comfort noise being sent to theMSC 2305 in the core network from the coordinating server 2304, itallows a limited backhaul bandwidth to be used for other mobilesubscribers and services. Silence, or a low-bandwidth audio track, orany other audio samples, or an instruction to provide comfort noisecould be used instead of comfort noise as described herein, in someembodiments.

In some embodiments, the call correlation-id is generated at thecoordinating server 2104 and encoded in as a User-User InformationElement (IE) in the SETUP message. The purpose of the User-User IE is toconvey information between a mobile station and the remote user. Thecall correlation-id is thus passed across an originating and aterminating call leg. The call correlation-id is removed before themessage received from the coordinating server 2204 at the base station2203 is forwarded to the UE2 2202. Supporting the User-User IE mayrequire provisioning in a HLR. However, if support for the User-User IEis not provisioned in the HLR, MSC 2205 in the core network may need tobypass a check for the subscribers so that user to user service can beused. The call correlation-id acts as a cookie and can be generated fromvarious information, for example, base station's IP address, an IMSI ofa calling subscriber, a MSISDN of the calling subscriber, a MSISDN ofthe called subscriber, timestamp of the call origination etc. The callcorrelation-id is stored in a cache or a database at the coordinatingserver 2104 where it was created originally. However, the user is notlimited to the examples given here for storing call correlation-id andcan use any available methods at the time of implementation.

FIG. 24 illustrates a scenario where one party of an established voicecall moves to a different base station and base stations hosting theparties of the voice call are managed by the same coordinating server,in accordance with some embodiments.

In some embodiments, a UE-A 2401 also referred as a UE1 2401 in thisdisclosure is in an established voice call with a UE-B 2402 alsoreferred as a UE2 2402 in this disclosure. Both the UE1 2401 and the UE22402 are camped on to a base station base station BS-1 2403. The basestation BS-1 is managed by a coordinating server 2404 and connectedthrough a wired or wireless backhaul system. The backhaul system may bea mesh backhaul system. The coordinating server 2404 is furtherconnected to a MSC 2405 and a SGSN 2406 in a mobile operator's corenetwork. RTP localization feature is provisioned and active for the basestation base station BS-1 2403 at the coordinating server 2404.Therefore, the RTP packets are switched locally at the base station2403. When the UE2 2402 moves to a different cell and camps on to a basestation base station BS-2 2407, because the UE1 2401 and the UE2 2402are no longer camped on to the same base station BS-1 2403, RTPlocalization functionality cannot be continued for the established voicecall between the UE1 2401 and the UE2 2402.

In this case, UE2 is moving from base station BS-1 to base station BS-2within same coordinating server. In this case the localization functionis assumed to be present in base station BS-1. After the UE2 moves toBS-2 the RTP localization will not apply. Table 2 lists the logicalsteps in accordance with some embodiments.

FIG. 25 illustrates a scenario where one party of an established voicecall moves to a different base station and base stations where partiesof the voice call are now camped on are managed by a differentcoordinating server, or one of the base station is macro base stationand managed by a different coordinating server or a radio networkcontroller (RNC), in accordance with some embodiments.

See TABLE 2 below for the logical steps to perform the operation inaccordance with some embodiments.

TABLE 2 1 UE1 & UE2 Registration, call setup for calls between UE1 & UE2with RTP localization 2 Relocation required message from BS-1 3Coordinating server notifies BS-1 to remove the linked call. As the BS-1knows the Relocation state, this can be performed locally. 4Coordinating server sends Relocation Request towards target base station(BS-2). In the relocation request, the RABs to be setup will beincluded. In the transport layer address the coordinating server's IPAddress is included. 5 BS-2 sends Relocation Request Ack. In the RABssetup, the transport layer IP Address will have BS-2's IP. 6 RelocationCommand request is send to BS-1. For CS call, data forwarding list andthe associated transport layer address (for forwarding packets) is notincluded.  7- Relocation detect & Relocation complete message sent fromBS-1. 9 TNL Update request/response messages. This will includecoordinating server's IP for the RAB transport layer address for UE1 10 TNL Update request/response messages. This will include coordinatingserver's IP for the RAB transport layer address for UE1 11  Iu Releasefor UE2

In some embodiments, a UE-A 2501 also referred as a UE1 2501 in thisdisclosure is in an established voice call with a UE-B 2502 alsoreferred as a UE2 2502 in this disclosure. Both the UE1 2501 and the UE22502 are camped on to a base station base station 2503. The base stationBS-1 2503 is managed by a coordinating server 2504 and connected througha wired or wireless backhaul system. The backhaul system may be a meshbackhaul system. The coordinating server 2504 is further connected to aMSC 2505 and a SGSN 2506 in a mobile operator's core network. RTPlocalization feature is provisioned and active for the base station BS-12503 at the coordinating server 2504. Therefore, the RTP packets areswitched locally at the base station BS-1 2503. When the UE2 2502 movesto a different cell and camps on to a base station BS-2 2507, becausethe UE1 2501 and the UE2 2502 are no longer camped on to the same basestation BS-1 2503, RTP localization functionality cannot be continuedfor the established voice call between the UE1 2501 and the UE2 2502.

FIG. 26 illustrates a call flow ladder diagram when a RTP localizationfunctionality is terminated as a result of one of party of anestablished voice call moves to a different cell and camps on to adifferent base station or NodeB, in accordance with some embodiments.

Table 3 lists the logical steps in accordance with some embodiments.

TABLE 3 1 UE1 & UE2 Registration and call setup for calls between UE1 &UE2 with RTP localization at BS-1 2 Measurement report is sent from UE.Based on measurement report Relocation required message is triggeredfrom BS-1 3 As the target cell-id is not managed by coordinating server,the Relocation required message is sent to MSC 4 MSC sends RelocationRequest towards target RNC. In the relocation request, the RABs to besetup will be included. In the transport layer address the MSC IPAddress is included. 5 RNC sends Relocation Request Ack. In the RABssetup, the transport layer IP Address will have RNC IP. 6 RelocationCommand request is send to coordinating server. For CS call, dataforwarding list and the associated transport layer address (forforwarding packets) is not included. 7 The Relocation Command message issent to BS-1. Again, for CS call data forwarding list is not included 8After processing the relocation command, the locally linked RTP will beterminated. This can be done internally by BS-1 or with an explicitmessage from coordinating server 9 Relocation complete & Iu Releasemessages

In some embodiments, messages are exchanged between a coordinatingserver 2604 and a base station BS-1 2603 to turn off RTP localizationfunctionality. The coordinating server 2604 is also previously referredas the coordinating server 2104, the coordinating server 2204, thecoordinating server 2304, the coordinating server 2404 and thecoordinating server 2504. The base station BS-1 2603 is previouslyreferred as the base station 2103, the base station 2203, the basestation 2303, the base station 2403 and the base station 2503. A UE12601 and a UE2 2602 are in an established voice call and RTPlocalization is active at the base station the BS-1 2603. The UE1 2601is previously referred as the UE1 2101, the UE1 2201, the UE1 2301, theUE1 2401 and the UE1 2501. The UE2 2602 is previously referred as theUE2 2102, the UE2 2202, the UE2 2302, the UE2 2402 and the UE2 2502. TheUE2 2602 now moves to a different cell and camps on a different basestation BS-2 2606. The base station BS-2 2606 may also be a NodeBmanaged by the same coordinating server managing the base station BS-12603 or a different coordinating server or RNC.

As the UE2 2602 is moving to a different cell, the base station BS-12603 receives RRC Measurement Report from the UE2 2602 and the basestation BS-1 2603 sends RANAP Relocation Required carrying a source anda destination cell ID as well as the base station ID information to thecoordinating server 2604. If a base station where the UE2 2602 ismoving, a target base station BS-2 2606, is managed by the coordinatingserver 2604 as well, the coordinating server 2604 sends a RANAPRelocation Request message to the target base station 2606. The RANAPRelocation Request carries information about RAB to be setup and thatincludes an IP Address of the coordinating server 2604 and a port numberallocated at the coordinating server 2604 for the UE2 2602. The targetbase station 2606 sends response RANAP Relocation Request Ackidentifying a success or a failure and also includes information of RABtransport layer parameters with IP address as the target base stationBS-2 2606's IP address and a port number allocated at the base stationBS-2 2606 for RTP. The coordinating server 2604 also sends to the basestation 2603 a RANAP RAB Assignment Request for the UE1 2601 carryingnew RAB transport layer parameters with IP Address as the coordinatingserver 2604's IP address and a port number assigned at the coordinatingserver 2604 for the UE1 801. Also, resources allotted at the basestation BS-1 2603 may be freed.

In some embodiments, when the base station BS-2 2606 is managed by adifferent coordinating server than the coordinating server managing thebase station BS-1 2603 or a RNC, as the UE2 2602 is moving to adifferent cell, the base station BS-1 2603 receives RRC MeasurementReport from the UE2 2602 and the base station BS-1 2603 sends RANAPRelocation Required carrying a source and a destination cell ID as wellas the base station ID information to the coordinating server 2604. If abase station where the UE2 2602 is moving, a target base station BS-22606, is managed by a different coordinating server or a RNC, thecoordinating server 2604 sends a RANAP Relocation Required carrying asource and a destination cell ID as well as the base station IDinformation to a MSC 2605. The MSC 805 completes the handover or cellrelocation procedure. The coordinating server 2604 also sends to thebase station BS-1 2603 a RANAP RAB Assignment Request for the UE1 2601carrying new RAB transport layer parameters with IP Address as thecoordinating server 2604's IP address and a port number assigned at thecoordinating server 2604 for the UE1 2601. Also, resources allotted atthe base station BS-1 2603 may be freed.

In a scenario where a UE1 is attached to base station BS-1 2503 and UE2is attached to macro coverage at NodeB-2 2507. After the CS Call issetup, UE2 moves from macro coverage to BS-1's coverage area.

In some embodiments, even though the both UE's are in the same BS-1'scoverage area after relocation, RTP Localization function may not beapplied. Any new call initiated after hand-in can be localized, in someembodiments.

TABLE 4 1 UE1 is registered with BS-1. UE2 is attached to macro cellcoverage with RNC. Initially call is setup between UE1 & UE2 2Relocation Request is sent from RNC to MSC. The transport layer addresswill contain RNC IP/Port. MSC Forwards the Relocation Request tocoordinating server. 3 Coordinating server send the Relocation Requesttowards BS-1 by including the transport layer address for coordinatingserver 4 BS-1 sends Relocation Request Ack. In the RABs setup, thetransport layer IP Address/Port of BS-1 will be included. 5 Coordinatingserver sends Relocation Request Ack. In the RABs setup, the transportlayer IP Address/Port of coordinating server will be included. 6Relocation Detect message is sent to RNC through coordinating server. 7BS-1 sends UTRAN Mobility Information message to UE to update the C-RNTI& U-RNTI and any other relevant IEs. 8 Relocation complete is sent toRNC from BS-1 (through coordinating server)

In another aspect, a UE1 is attached to a base station BS-1 and a UE2 isinitially attached to a base station BS-2/NodeB-2. The BS-1/NodeB-1 andthe BS-2/NodeB-2 are managed by different coordinating servers or BS-1for example is managed by a coordinating server and the BS-2 is managedby a RNC. A voice call is established between the UE1 and the UE2. TheUE2, during the established voice call, moves to a cell served by theBS-1 causing the RNC to send a RANAP Relocation Request to a MSC/SGSN.The RANAP Relocation Request may include CN Domain Indicator, Source RNCto Target RNC transparent container and RAB to be setup specifying RABTransport Layer Parameter as IP address and port number of RNC. The MSCforwards the RANAP Relocation Request message to the coordinating serverand the coordinating server forwards the same to the base station BS-1but replacing RAB Transport Layer Parameters for IP Address and portNumber with the same for coordinating server. The BS-1 responds with aRANAP Relocation Request Ack message and includes RAB Transport Layerparameters with IP Address and port number of the base station BS-1. Thecoordinating server forwards the RANAP Relocation Request Ack to the MSCbut replaces RAB Transport Layer parameters with IP Address and portnumber of the coordinating server. The MSC forwards the received RANAPRelocation Request Ack to the RNC. The base station BS-1 further sendsRANAP Relocation Detect message to the RNC through the coordinatingserver and the MSC. The base station BS-1 further sends a RRC UTRANMobility Information message to the UE2 to update Cell Radio NetworkTemporary Identities (C-RNTI) and UTRAN Radio Network TemporaryIdentities (U-RNTI) and other relevant IEs. The UE2 sends RRC UTRANMobility Information Confirmation triggering the BS-1 to send a RANAPRelocation Complete to RNC through the coordinating server and the MSC.RTP localization is not enabled in this case even though the UE1 and theUE2 are both camped on to the same base station BS-1.

In some embodiments, the coordinating server 2004 may determine toenable RTP localization at the base station 2003 based on a multi-factoranalysis. The coordinating server may perform multi-factor analysisbased on what RAT is involved, availability of mesh links from the basestation to the core network, need of transcoding between the originatingand the terminating leg of the call of the under-surveillancesubscriber. The multi-factor analysis at the coordinating server mayalso depend on computing power at the base station, abilities to storeRTP streams at the base status, the base station's power source status,call pattern of the under-surveillance UE, etc. The coordinating servermay determine to disable RTP performing cost-benefit analysis based onwhat RAT is involved, availability of mesh links from the base stationto the core network, need of transcoding between the originating and theterminating leg of the call of the subscriber. The multi-factor analysismay be based on policies received from a PCRF, in some embodiments.

Lawful Intercept (LI)

In case a Lawful Intercept is configured for a subscriber on thecoordinating server, it may instruct the base station not to handle theRTP traffic locally for this subscriber, so that all the RTP trafficgoes to the MSC as shown in FIG. 19 . The MSC on receiving this trafficshould be able to duplicate the streams towards the LI server.

In some embodiments, when lawful intercept is enabled for either a UE1or a UE2, the coordinating server 2004 may disable switching of RTPpackets locally at the base station for voice calls involving the UE1 orthe UE2 even though the UE1 and the UE2 are latched to the same basestation and switching of RTP packets locally may be supported ingeneral. When lawful intercept is enabled at the base station level, thecoordinating server 2004 may disable switching of RTP packets locallyfor all calls from UEs latched to the base station. The coordinatingserver may receive information about lawful intercept for a base stationlevel interception or the subscriber level interception from operator LIplatform via a message identifying sequence ID of the message, lawfulintercept status. The message may further comprise RAN identifierinformation identifying the base station. The message may furtheridentify a subscriber by a combination of source or destination IPAddresses and/or source or destination port number. The coordinatingserver may respond the lawful intercept request message from theoperator lawful intercept server with a message comprising success orfailure code identifying reasons e.g. resource unavailable, source ordestination IP or port not active etc. In some cases, the responsemessage from the coordinating server may further include a reason fieldclearly identifying the failure reason.

For lawful intercept, the coordinating server may instruct the basestation to clone RTP packets of the RTP localized call for theunder-surveillance UE at the base station 2003 and send the clonedstream to the coordinating server 2004. The coordinating server 2104then sends the cloned RTP packets from the base station to the LI serveror to the MSC in the core network. An interface or endpoint details willbe provisioned at the coordinating server to send RTP streams from theunder-surveillance UEs through a static or dynamic configuration.

In some embodiments, when lawful intercept is enabled for either a UE1or a UE2, the coordinating server 2104 may enable RTP localization atthe coordinating server based on the multi-factor analysis as describedabove. The coordinating server may hairpin the RTP streams itself andsend compressed RTP streams the LI server or to the MSC in the corenetwork. An interface or endpoint details will be provisioned at thecoordinating server to send RTP streams from the under-surveillance UEsthrough a static or dynamic configuration.

In some embodiments, when lawful intercept is enabled for either a UE1or a UE2, the coordinating server 2104 may enable RTP localization atthe base station based on the multi-factor analysis as described above.The coordinating server may instruct the base station to record andstore the RTP streams packets locally and forward later to thecoordinating server 2104 as a compressed RTP data streams. Thecoordinating server may forward the received compressed RTP data streamsto the LI server or the core network as provisioned.

FIG. 27 shows a coordinating server to a provisioning gateway interfacecreation and the message flow ladder diagram when a RTP localizationfunctionality is enabled for a base station, in accordance with someembodiments.

In some embodiments, as shown in FIG. 27 , a coordinating server 2704that could be a coordinating server of the cluster of coordinatingservers initiates a connection to an active PGW 2705 by sending a loginrequest and authenticating with a username and a password. If there isno response from the active provision gateway 2705, the coordinatingserver 2704 attempts to establish a connection to a standby provisioninggateway 2706. In some aspects of the disclosed subject matter, eachcoordinating server in the cluster of coordinating servers has itsseparate interface to the active or standby provisioning gateway orboth. In some aspects of the disclosed subject matter, only one of thecoordinating server of the cluster of coordinating server has interfaceto the active or standby provisioning gateway or both.

In some embodiments, as shown in FIG. 27 , when a UE 2701 is attached toa base station 2703, the base station 2703 sends a UE RegistrationRequest to a coordinating server 2704. The UE Registration Requestcontains IMSI information for the UE 2701. The coordinating server 2704sends a web-service request to a provisioning gateway 2705 to get MSISDNinformation for the UE 2701. The web-service response from theprovisioning gateway 2705 contains a MSISDN and other relevantinformation for the UE 2701. The coordinating server 2704 creates anassociation of the IMSI and the MSISDN and stores in a memory or adatabase. Though, the disclosure describes a web-service request toquery the provisioning gateway 2705 from the coordinating server 2704, aperson skilled in the art may recognize and use other methods known inthe field to query and receive a response.

In some embodiments, the coordinating server 2704 queries theprovisioning gateway 2703 only for a base station which has RTPlocalization enabled and thereby reducing the load on the network.

In some embodiments, the coordinating server queries HLR over mobileapplication part (MAP) interface to create IMSI-MSISDN mapping.

In some embodiments, when a UE is deregistered, an entry in a cache or adatabase may not be removed immediately.

FIG. 28 illustrates a call flow diagram when RTP localization is enabledusing an IMSI and a MSISDN mapping, in accordance with some embodiments.

In some embodiments, A UE1 2801 and a UE2 2802 are camped on a basestation 2803 following a UE Registration procedure. The base station2803 is managed by a coordinating server 2804 and a MSC 2805 is in amobile operator's core network. When the UE1 2801 initiates a voicecall, the UE1 2801 sends RRC Setup message carrying Called Party Address(CdPA) MSISDN to the base station 2803. The base station 2803 forwardsthe message to the coordinating server 2804 as a RANAP/NAS Setup messageand incudes CdPA MSISDN. The coordinating server 2804 creates anoriginating MO call leg and forwards the received NAS Setup message tothe MSC 2805. The MSC 2805 locates where the CdPA MSISDN subscriber iscurrently located through paging operation and sends NAS Setup messageto the coordinating server 2804 because the CdPA MSISDN is latched atthe base station 2803 managed by the coordinating server 2804. Thecoordinating server 2804 does a lookup for IMSI for the CdPA MSISDN andfinds the record. The coordinating server 2804 also does a comparison ofa Calling Party Address (CgPA) MSISDN in the received NAS Setup messagefrom the MSC 2805 and Mobile Originated (MO) MSISDN from the originatingleg. If the CgPA MSISDN and MO MSISDN are same, the coordinating server2804 links the MO and MT call legs and instructs the base station 1203to perform RTP localization as described before, if the IMSI based onCgPA MSISDN indicates that the UE1 2801 and the UE2 2802 are at the samebase station 2803.

In some embodiments, a call correlation-id can be exchanged acrossoriginating and terminating legs using dynamic RTP payload type insteadof a User-User IE in the RANAP Initial UE message from the coordinatingserver 2104 to the MSC 2105 in the core network in accordance with someembodiments. For example, dynamic RTP payload type 121 can be used asshown below

Real-Time Transport Protocol

10 . . . =Version: RFC 1889 Version (2)

. . . 0 . . . =Padding: False

. . . 0 . . . =Extension: False

. . . 0000=Contributing source identifiers count: 0

0 . . . =Marker: False

Payload type: DynamicRTP-Type-121 (121)

Sequence number: 25330

Timestamp: 0

Synchronization Source identifier: 0x00000000 (0)

In some embodiments, RTP Payload type 96-127 can be used for dynamicpayload types. One payload type (assume payload type 121) can be used bythe coordinating server 2104 to exchange the call correlation-idinformation after the call is connected. For use of dynamic payloadtypes for associating the originating and terminating leg of the call, amedia gateway in a mobile operator's core network may be required totransparently pass a RTP payload to the coordinating server 2104. TheRTP payload may include IP Address for the UE1 2101 as received from thebase station 2103 to pass the call correlation across the originatingand the terminating legs. The IP Address for the UE1 2101 is only usedhere as an example and the coordinating server can use any informationas a cookie for associating the originating and the terminating calllegs. After the correlation of the originating and terminating legs, ifthe coordinating server 2104 determines that the originating and theterminating UEs are latched to the same base station, RAB modificationprocess may be initiated at the base station. The coordinating server2104 sends a transport network layer (TNL) Update request to the basestation 2103 to update RAB transport parameters for UE1 2101 with thebase station IP Address and Port for the UE2 2102 and TNL Update requestto the base station 2103 to update RAB transport parameters for the UE22102 with the base station IP Address and Port for the UE1 2101. Uponsuccessful RAB modification process, RTP packets between the UE1 2101and the UE2 2102 are switched locally at the base station 2103. Thecoordinating server 2104 transmits comfort noise to the MSC 2105 in thecore network and thus helps saving backhaul bandwidth and getting Iuconnections released.

In accordance with some embodiments, the call correlation-id between theoriginating and terminating leg can be exchanged using CSRC list in theRTP header. CSRC list identifies the contributing sources for thepayload contained in the packet and SSRC identifies all sources thatwere mixed together create a packet and allows the correct sourceindication at the receiver. After the call is connected, thecoordinating server 2104 will add CSRC in the RTP packet to the corenetwork. When the coordinating server 2104 receives the RTP packet backfrom the core network for the terminating leg, based on the CSRC value,the coordinating server 2104 determines that a originating and aterminating base station for this voice call is same and RTP streamsneeds to be switched locally. The coordinating server 2104 thereforeinitiates RAB Modification procedure as described above.

In some embodiments, the coordinating server 304 may transmit comfortnoise towards the core network using a different SSRC. It is alsorequired that MSC supports User-User IE in the CC Setup message in theterminating leg towards the coordinating server. In addition, the basestation 2103 may also support jitter buffer management. If RTP frameswith multiple SSRC is presented to the base station 2103, it will beable to play the RTP stream. While RAB modification is initiated by thecoordinating server for switching RTP streams locally at the basestation, there may be a loss of initial RTP payload packets.

FIG. 29 is a flowchart of RTP localization activation procedure, inaccordance with some embodiments. User Equipments UE1 and UE2 are campedon to the base station referenced in the flowchart of FIG. 29 . The basestation is further managed by a coordinating server that appears as aradio network controller to the base station. The base station may alsobe referenced by other names such as a NodeB, a small cell, a femto cellor etc. At step 2901, when the UE1 initiates a voice call to the UE2,the coordinating server receives NAS Setup message from the basestation. At step 2902, the coordinating server processes the receivedNAS Setup message and creates a call correlation-id. The callcorrelation-id is a unique identifier that helps to identify a mobileoriginated leg and a mobile terminated leg as the call correlation-id ispassed from the mobile originated leg to the mobile terminated legthrough the core network. The call correlation-id can be generated basedon various information that may help identify the base station where thecall was originated. The information, therefore, available to build callcorrelation-id may be a IP address of the base station, radio accessnetwork (RAN) identifier of the base station. The call correlation-id isstored for a limited time in a cache or database. At step 2903, thecoordinating server encodes NAS Setup message to send to the corenetwork with the call correlation-id set in a User-User IE field andsends the NAS Setup message to a MSC in the core network. At step 2904,as the coordinating receives NAS Setup message for a called mobilesubscriber camped on to the base station identified at step 2901, thecoordinating server decodes the received NAS Setup Message's User-UserIE to get a call correlation-id value. At step 2905, the coordinatingserver performs a search for the decoded call correlation-id to find arecord of an entry so that the coordinating server may determine whetherthe mobile originating and mobile terminating legs are processed at thesame coordinating server. Upon finding a valid record and determiningthat the mobile originating and the mobile terminating legs are at thesame coordinating server, further inquiry is made to find if the basestation is same where a calling mobile subscriber, the UE1, and a calledmobile subscriber, the UE2, are camped on. The call correlation-ididentifies the base station where the calling mobile subscriber iscamped on and a paging operation to set up a mobile terminated legidentifies the base station where the called mobile subscriber is campedon. Therefore, based on the call correlation-id, the coordinating servercan successfully decide to activate RTP localization if the UE1 and theUE2 are at the same base station or to continue its normal call setupprocedure without RTP localization, as shown at step 2908. At step 2906,if the coordinating server determined to activate RTP localization, itlinks originating and terminating legs i.e. identifies that the calllegs are in RTP localized call, for a subsequent action later asdiscussed further in this disclosure. At step 2907, the coordinatingserver initiates RAB modification procedure for the UE1 and the UE2. Thecoordinating servers sends RAB assignment request messages for the UE1and the UE2 to the base station and include transport network layerparameters as the IP address of the base station. The RAB assignmentrequest sent to the base station for the UE1 includes port number of theUE2's RTP connection at the base station; the RAB assignment requestsent to the base station for the UE2 includes port number of the UE1'sRTP connection at the base station. The coordinating server may sendcomfort noise packets to the core network to avoid release of the Iuconnection.

At step 2905, the coordinating server may consider additional criteriato activate RTP localization. The additional criteria may be based onvarious factors. The factors affecting RTP stream's route selection andRTP localization for example are cost associated with routing the RTPtraffic over the backhaul system, QoS over the selected route, contractsamong various operators for billing and usage of their networkresources, time of the day etc. Whether the coordinating server enablesRTP localization at the base station may also depends upon transcodingrequirement based on the negotiated RTP codecs. If transcoding needed,the coordinating server may enable RTP localization either at the basestation or at the coordinating server. The coordinating server may actas a media gateway controller and provide transcoding service usingmedia gateways. The coordinating server may also act as a media gatewayand provide transcoding. The coordinating server, due to its uniqueposition in the network, positioned between the radio access network andthe core network, may enable RTP localization based on models generatedconsidering network topology, types of traffic, traffic load fromvarious base stations managed by the coordinating server, networkoutages, availability of backhaul for internet breakout, sessionencryption requirements etc. The models may be generated based on eachfactor computed alone or in any combination of the factors. For RTPlocalization among base stations with different RA in a base stationgroup, the coordinating server may perform localization of RTP at thecoordinating server instead of the base station.

FIG. 30 is a flowchart of RTP localization activation procedure, inaccordance with some embodiments. At step 3001, a coordinating serverregisters with a provisioning gateway by authenticating itself with auser and password to create an interface to the provisioning gateway.The provisioning gateway is in communication to a home location register(HLR) of a mobile operators' core networks. The provisioning gatewayreceives information about mobile subscribers' IMSI and MSISDN from theHLR. Mobile subscriber may also be referred by other names such as auser equipment (UE), mobile device etc. At step 3102, the coordinatingserver receives a registration request from a mobile subscriber as themobile subscriber camps on a base station managed by the coordinatingserver. Upon successful registration of the mobile subscriber at thecoordinating server, the coordinating server queries the provisioninggateway to receive the registered mobile subscriber's MSISDN informationto associate with the IMSI of the mobile subscriber received in theregistration request. The query from the coordinating server to theprovision gateway may be a web-service request using Simple ObjectAccess Protocol (SOAP) or Representational State Transfer (REST). Thecoordinating server may query the provision gateway over MobileApplication Part (MAP) interface as well to receive the registeredmobile subscriber's MSISDN information to associate with the IMSI of themobile subscriber received in the registration request. Upon receivingresponse from the provisioning gateway, the coordinating server createsan association between IMSI and MSISDN for the mobile subscriber. Thecoordinating server may store the association in RAM, in database, ormay implement using any well-known methods such as list, hash-table, mapetc. IMSI may also identify the base station where the mobile subscriberis currently latched. At step 3103, when the coordinating serverreceives a NAS Setup message from the core network, it extracts callingparty address (CgPA) MSISDN from the NAS Setup message. At step 3104, itperforms search for the (CgPA) MSISDN in a list of CgPA MSISDN for themobile originating legs at the coordinating server. At step 3105, if noentry found in the list of CgPA MSISDN for the mobile originated legs atthe coordinating server having the CgPA MSISDN as received in the NASSetup message from the core network, the coordinating server decidesthat RTP localization feature cannot be activated and continuesprocessing normally as per the standards. At Step 3106, the coordinatingserver further verifies by finding IMSI based on the calling mobilesubscriber's and called mobile subscriber's MSISDN to determine if thecalling and called mobile subscribers are camped on the same basestation. At step 3107, if calling and called mobile subscriber arecamped on the same base station, the coordinating server activates RTPlocalization and links the mobile terminated leg with the mobileoriginating leg for subsequent operation as discussed below in thisdisclosure. At step 3108, the coordinating server performs RABmodification for the calling and called mobile subscribers at the basestation. The coordinating servers sends RAB assignment request messagesfor the calling and the called mobile subscribers to the base stationand include transport network layer parameters as the ip address of thebase station. The RAB assignment request sent to the base station forthe calling mobile subscriber includes port number of the called mobilesubscriber's RTP connection at the base station; the RAB assignmentrequest sent to the base station for the called mobile subscriberincludes port number of the calling mobile subscriber's RTP connectionat the base station. The coordinating server may send comfort noisepackets to the core network to avoid release of the Iu connection.

FIG. 32 is a flowchart of RTP localization deactivation procedure, inaccordance with some embodiments. At step 3201, a coordinating serverreceives Relocation command and Iu release from a base station where aUE1 and UE2 are in a RTP localized call. At Step 3202, the coordinatingserver determines if a target base station where the UE2 is moving ismanaged by the coordinating server. If no, at step 3203, thecoordinating server sends Relocation Required to core network tocomplete handover, else the coordinating server sends Relocation Requestto the target base station to complete handover at Step 3204. At step3205, the coordinating server sends Relocation Command to the basestation and also sends Iu Release upon completion of handover. At step3206, the coordinating server checks whether the UE2 was in a RTPlocalized call, and if yes, at step 3207, the coordinating server sendsRAB medication request to the base station for UE1. RAB modificationRequest to the base station for UE1 follows RAB modification for theoriginating leg as described above and includes the coordinatingserver's IP address and port in RAB Modify list.

Alternatives

In the present disclosure, the words “NodeB” or “eNodeB” are used torefer to a cellular base station. However, one of skill in the art wouldappreciate that it would be possible to provide the same functionalityand services to other types of base stations, specifically to BTSes,non-3GPP base stations, CDMA base stations, CDMA2000 base stations,Wi-Fi access points, and home eNodeBs (HeNodeBs), as well as anyequivalents.

While the present disclosure uses the term “small cell,” this term isused merely to illustrate the concepts herein, and nothing is impliedregarding size, power level etc. for any cells that could be used withthe disclosed systems and methods, i.e. “small cell” may be interpretedas including macro cells, femto cells, multi-radio access technology(RAT) access nodes including 2G/3G/4G/Wi-Fi/LTE, indoor cells, outdoorcells, etc.

Once the coordinating server enabled RTP localization based on themulti-factor analysis, the coordinating server may be in communicationwith the policy server or policy engine and receives rules for enablingRTP localization functionality. The coordinating server, may stillinstruct the base station to perform the billing operation and sendbilling record and other relevant analytics data such as QoS, callcompletion success rate, interference etc. for radio network managementby the core network.

Various alternative embodiments are also contemplated by the inventors.For example, certain functions may be performed at a multi-radio accesstechnology node (multi-RAT) node, instead of at a base stationmanagement gateway. The base station management gateway maysubstantially take the form of the described Parallel Wirelesscoordinating server. The base station management gateway may be avirtualization server. The functions of the base station managementgateway may be broken up and spread across multiple network nodes, ormultiple software or hardware modules within the same network node, andmay be physically located in a single location, or multiple locations.The network node may be in the data path located between the radioaccess network (RAN) and the core network, in some embodiments, or maybe located at another location in the network. A high-bandwidth wiredconnection may be used for backhaul, such as coaxial cable, fiber opticcable, or Ethernet, or a reduced-bandwidth wireless connection, such asmicrowave, line-of-sight, or other physical connections may be used asbackhaul.

The protocols described herein may be optimized for greater or lesserlatency, for more or fewer mesh nodes, for more or fewer data streams,and other alternatives. In some embodiments, these optimizations may beperformed at the eNodeB, at the base station management gateway, withina function performing radio resource allocation and coding selection, orat another location. In some embodiments, a base station managementgateway may identify and initiate power adjustments to improve channelquality.

In some embodiments, the mesh network nodes may provide complete orpartial guesses at what paths are the optimal or best paths during aparticular time interval, and may be enabled to send messages back tothe base station management gateway to communicate these complete orpartial guesses.

In some embodiments, the base stations described herein may becompatible with a 3GPP UMTS or Long Term Evolution (LTE) radiotransmission protocol or air interface. The LTE-compatible base stationsmay be eNodeBs. In addition to supporting the 3G WCDMA protocol, thebase stations may also support other air interfaces, such as LTE,UMTS/HSPA, CDMA/CDMA2000, GSM/EDGE, GPRS, EVDO, other 3G/2G, legacy TDD,or other air interfaces used for mobile telephony. In some embodiments,the base stations described herein may support Wi-Fi air interfaces,which may include one of 802.11 a/b/g/n/ac/ad/af/ah. In someembodiments, the base stations described herein may support 802.16(WiMAX), or other air interfaces. In some embodiments, the base stationsdescribed herein may provide access to land mobile radio(LMR)-associated radio frequency bands. In some embodiments, the basestations described herein may also support more than one of the aboveradio frequency protocols, and may also support transmit poweradjustments for some or all of the radio frequency protocols supported.

The above-described features and applications can be implemented assoftware processes that are specified as a set of instructions recordedon a computer-readable storage medium (also referred to as computerreadable medium). When these instructions are executed by one or moreprocessing unit(s) (e.g. one or more processors, cores of processors, orother processing units), they cause the processing unit(s) to performthe actions indicated in the instructions. Examples of computer readablemedia include, but are not limited to, CD-ROMs, flash drives, harddrives, RAM chips, EPROMs, etc. The computer-readable media does notinclude carrier waves and electronic signals passing wirelessly or wiredconnections.

In the specification, the term “software” is meant to include firmwareresiding in read-only memory or applications stored in magnetic storageor flash storage, for example, a solid-state drive, which can be readinto memory for processing by a processor. Also, in someimplementations, multiple software technologies can be implemented assub-parts of a larger program while remaining distinct softwaretechnologies. In some implementations, multiple software technologiescan also be implemented as separate programs. Finally, any combinationof separate programs that together implement a software technologydescribed here is within the scope of the subject technology. In someimplementations, the software programs, when installed to operate on oneor more electronics systems, define one or more specific machineimplementations that execute and perform the operations of the softwareprograms.

A computer program (also known as program, software, softwareapplication, script, or code) can be written in any form of programminglanguage, including compiled or interpreted languages, declarative orprocedural languages, and it can be deployed in any form, including as astandalone program or as a module, component, subroutine, object, oranother unit suitable for use in a computing environment. A computerprogram may, but need not correspond to a file in a file system. Aprogram can be stored in a portion of a file that holds other programsor data (e.g., one or more scripts stored in a markup languagedocument), in a single file dedicated to the program in question, or inmultiple coordinated files (e.g., files that store one or more modules,sub-programs, or portions of code). A computer program can be deployedto be executed on one computer or on multiple computers that are locatedat one site or distributed across multiple sites and interconnected by acommunication network.

These functions described above can be implemented in digital electroniccircuitry, in computer software, hardware, or firmware. The techniquescan be implemented using one or more computer program products.Programmable processors and computers can be included in or packaged asmobile devices. The process and logic flows can be performed by one ormore programmable processors and by one or more programmable logiccircuitry. General and special purpose computing devices and storagedevices can be interconnected through communication networks.

Some implementations include electronic components, for examplemicroprocessors, storage and memory that store computer programinstructions in a machine-readable or computer-readable medium(alternatively referred to as computer-readable storage media,machine-readable media, or machine-readable storage media). Someexamples of such computer-readable media include RAM, ROM, read-onlycompact discs (CD-ROM), readable compact discs (CD-R), rewritablecompact discs (CD-RW), read-only digital versatile discs (e.g., DVD-ROM,dual-layer DVD-ROM), a variety of recordable/rewritable DVDs (e.g.DVD-RAM, DVD-RW, DVD+RW, etc.), flash memory (e.g., SD cards, mini-SDcards, micro-SD cards, etc.), magnetic or solid-state hard drives,read-only and recordable Blu-Ray® discs, ultra-density optical discs,any other optical or magnetic media, and floppy disks. Thecomputer-readable media can store a computer program that is executed byat least one processing unit and includes sets of instructions forperforming various operations. Examples of computer programs or computercode include machine code, for example is produced by a compiler, andfiles including higher-level code that are executed by a computer, anelectronic component, or a microprocessor using an interpreter.

While the above discussion primarily refers to microprocessor ormulti-core processors that execute software, some implementations areperformed by one or more integrated circuits, for example applicationspecific integrated circuits (ASICs) or field programmable gate arrays(FPGAs). In some implementations, such integrated circuits executeinstructions that are stored in the circuit itself.

As used in this specification and any claims of this application, theterms “computer”, “server”, “processor”, and “memory” all refer toelectronic or other technological devices. These terms exclude people orgroups of people. For the purpose of the specification, the termsdisplay or displaying means displaying on an electronic device. As usedin this specification and any claims of this application, the terms“computer-readable media” and “computer readable medium” are entirelyrestricted to tangible, physical objects that store information in aform that is readable by a computer. These terms exclude any wireless,wired download signals, and any other ephemeral signals.

To provide for interaction with a user, implementations of the subjectmatter described in this specification can be implemented on a computerhaving a display device, e.g., a CRT (cathode ray tube) or LCD (liquidcrystal display) monitor, or any other available monitor types, fordisplaying information to the user and a keyboard and a pointing device,e.g., mouse or trackball, by which the user can provide input to thecomputer. Other kinds of devices can be used to provide for interactionwith a user as well; for example, feedback provided to the user can beany form of sensory feedback, e.g., visual feedback, tactile feedback,or auditory feedback; and input from the user can be received in anyform, including acoustic, speech, or tactile input. In addition, acomputer can interact with a user by sending documents to and receivingdocuments from a device that is used by the user; for example, bysending web pages to a web browser on a user's client device in responseto requests received from the web browser.

The subject matter described in this specification can be implemented ina computing system that includes a back-end component, e.g., as a dataserver, or that includes a middleware component, e.g., an applicationserver, or that includes a front-end component, e.g., a client computerhaving a graphical user interface or a Web browser through which a usercan interact with an implementation of the subject matter described inthis specification, or any combination of one or more such back-end,middleware, or front-end components. The components of the system can beinterconnected by any form or medium of digital data communication,e.g., a communication network. Examples of communication network includea local area network (“LAN”), an inter-network (e.g., the Internet), andpeer-to-peer networks (e.g., ad-hoc peer-to-peer networks).

The computing system can include clients and servers. A client andserver are generally remote from each other and typically interactthrough a communication network. The relationship of client and serverarises by virtue of computer programs running on the respectivecomputers and having a client-server relationship to each other. In someaspects of the disclosed subject matter, a server transmits data (e.g.,an HTML page) to a client device (e.g., for purpose of displaying datato and receiving user input from a user interacting with the clientdevice). Data generated at the client device (e.g., a result of the userinteraction) can be received from the client device at the server.

It is understood that any specific order or hierarchy of steps in theprocesses disclosed is an illustration of example approaches. Based upondesign preferences, it is understood that the specific order orhierarchy of steps in the processes may be rearranged, or that allillustrated steps be performed. Some of the steps may be performedsimultaneously. For example, in certain circumstances, multitasking andparallel processing may be advantageous. Moreover, the separation ofvarious system components illustrated above should not be understood asrequiring such separation, and it should be understood that thedescribed program components and system can generally be integratedtogether in a single software product or packaged into multiple softwareproducts.

Various modifications to these aspects will be readily apparent, and thegeneric principles defined herein may be applied to other aspects. Thus,the claims are not intended to be limited to the aspects shown herein,but is to be accorded the full scope consistent with the languageclaims, where reference to an element in singular is not intended tomean “one and only one” unless specifically so states, but rather “oneor more.” Unless expressly stated otherwise, the term “some” refers toone or more. Pronouns in the masculine (e.g., his) include the feminineand neuter gender (e.g., her and its) and vice versa. Headings andsubheadings, if any, are used for convenience only, and do not limit thesubject technology.

A phrase, for example, an “aspect” does not imply that the aspect isessential to the subject technology or that the aspect applies to allconfigurations of the subject technology. A disclosure relating to anaspect may apply to all configurations, or one or more configurations. Aphrase, for example, an aspect may refer to one or more aspects and viceversa. A phrase, for example, a “configuration” does not imply that suchconfiguration is essential to the subject technology or that suchconfiguration applies to all configurations of the subject technology. Adisclosure relating to a configuration may apply to all configurationsor one or more configurations. A phrase, for example, a configurationmay refer to one or more configurations and vice versa.

The foregoing discussion discloses and describes merely exemplaryembodiments of the present invention. In some embodiments, softwarethat, when executed, causes a device to perform the methods describedherein may be stored on a computer-readable medium such as a computermemory storage device, a hard disk, a flash drive, an optical disc, orthe like. As will be understood by those skilled in the art, the presentinvention may be embodied in other specific forms without departing fromthe spirit or essential characteristics thereof. For example, wirelessnetwork topology can also apply to wired networks, optical networks, andthe like. The methods may apply to LTE-compatible networks, toUMTS-compatible networks, or to networks for additional protocols thatutilize radio frequency data transmission. Various components in thedevices described herein may be added, removed, or substituted withthose having the same or similar functionality. Various steps asdescribed in the figures and specification may be added or removed fromthe processes described herein, and the steps described may be performedin an alternative order, consistent with the spirit of the invention.Accordingly, the disclosure of the present invention is intended to beillustrative of, but not limiting of, the scope of the invention, whichis specified in the following claims.

What is claimed is:
 1. A method, comprising: at a coordinating serversituated as a gateway between a first base station and a core network,receiving an originating leg setup message for an originating leg bearerfrom the first base station for a first user equipment (UE) attached tothe first base station, the originating leg setup message including afirst call correlation identifier, the first UE registered with thecoordinating server, sent when the first UE initiates a voice call to asecond UE, the second UE also registered with the coordinating server;creating, at the coordinating server, an association between anInternational Mobile Subscriber Identity (IMSI) of the second UE and aMobile Station International Subscriber Directory Number (MSISDN) of thesecond UE; extracting a second call correlation identifier from aterminating leg setup message containing the IMSI of the second UE for aterminating leg bearer received from the core network by retrieving theMSISDN of the second UE based on the association of the IMSI of thesecond UE and the MSISDN of the second UE at the coordinating server;determining a real time protocol (RTP) localization status for theoriginating leg bearer and the terminating leg bearer based onperforming a comparison between the second call correlation identifierof the terminating leg and the stored first call correlation identifierof the originating leg; and sending transport layer assignment messagesto the first base station to redirect RTP packets from the first UE tothe second UE via the terminating leg bearer without the RTP packetstransiting the core network, thereby localizing the RTP packets.
 2. Themethod of claim 1, further comprising encoding the first callcorrelation identifier into the originating leg setup message.
 3. Themethod of claim 1, wherein the setup message is a non-access stratum(NAS) setup message, the first base station is a NodeB, the bearermodification message is a Universal Mobile Telecommunications Service(UMTS) radio access bearer (RAB) modification message.
 4. The method ofclaim 1, wherein the first call correlation identifier is encoded in aUser-User information element (IE) in the originating leg setup message,and further comprising forwarding, by the core network, the originatingleg setup message as the terminating leg setup message.
 5. The method ofclaim 1, wherein the transport layer assignment messages to the firstbase station include an Internet Protocol (IP) address of a serving basestation for the second UE, and further comprising sending transportlayer assignment messages to the serving base station for the second UEto redirect second RTP packets from the second UE to the first UE viathe originating leg bearer without the second RTP packets transiting thecore network.
 6. The method of claim 1, further comprising performingradio access bearer (RAB) modification based on the determination of theRTP localization status by sending RAB assignment requests to the basestation for the first UE, and wherein the transport layer assignmentmessages are RAB modification messages.
 7. The method of claim 1,wherein the second UE is also attached to the first base station, andfurther comprising performing radio access bearer (RAB) modificationbased on the determination of the RTP localization status by sending RABassignment requests to the base station for the first UE and the secondUE.
 8. The method of claim 1, wherein the second UE is also attached tothe first base station and the RTP packets are redirected internallywithin the first base station.
 9. The method of claim 1, wherein thefirst base station and the second base station are a single base stationusing a single radio access technology.
 10. The method of claim 1,further comprising redirecting the RTP packets as an RTP stream routedfrom the first base station to a second base station via a mesh network.11. The method of claim 1, further comprising sending comfort noise RTPpackets to the core network from the coordinating server based on thedetermination of the RTP localization status.
 12. The method of claim 1,further comprising receiving a Relocation Required message from thefirst base station for the first UE in a RTP localized call between thefirst UE and the second UE, caused by the first UE being handed over toa second base station.
 13. The method of claim 1, further comprisingproviding an inter-RAT handover of the first UE to one of a Wi-Fi radioaccess technology (RAT), a Long Term Evolution RAT using Voice over LTE(VoLTE), or a 2G RAT, and providing transcoding of the RTP packets toenable the inter-RAT handover.
 14. The method of claim 1, furthercomprising requesting an International Mobile Subscriber Identity (IMSI)of the first UE and a Mobile Station International Subscriber DirectoryNumber (MSISDN) of the first UE from a provisioning server using aHyperText Transfer Protocol web services protocol.
 15. The method ofclaim 1, further comprising providing billing and policy enforcement ofthe RTP packets without the RTP packets transiting the core network. 16.The method of claim 1, further comprising providing lawful intercept ofthe RTP packets by copying the RTP packets and sending the copied RTPpackets to the core network asynchronously.
 17. The method of claim 1,further comprising providing lawful intercept of the RTP packets bysending compressed RTP packets to the core network.
 18. A method,comprising: at a coordinating server situated as a gateway between afirst base station and a core network: receiving an originating legsetup message for an originating leg bearer from the first base stationfor a first user equipment (UE) attached to the first base station, theoriginating leg setup message including a first call correlationidentifier, the first UE registered with the coordinating server, sentwhen the first UE initiates a voice call to a second UE, the second UEalso registered with the coordinating server; creating a first callcorrelation identifier based on a called party MSISDN and storing thefirst call correlation identifier in association with the first UE;creating, at the coordinating server, an association between anInternational Mobile Subscriber Identity (IMSI) of the second UE and aMobile Station International Subscriber Directory Number (MSISDN) of thesecond UE; extracting a second call correlation identifier from aterminating leg setup message for a terminating leg bearer received fromthe core network by retrieving the MSISDN of the second UE based on theassociation of the IMSI and MSISDN of the second UE at the coordinatingserver; determining a real time protocol (RTP) localization status forthe originating leg bearer and the terminating leg bearer based onmatching the second call correlation identifier of the terminating legagainst the stored first call correlation identifier of the originatingleg; and sending transport layer assignment messages to the first basestation to redirect RTP packets from the first UE to the second UE viathe terminating leg bearer without the RTP packets transiting the corenetwork, thereby localizing the RTP packets.